Functional status, postural stability and falls among older adults with glaucoma

Visual impairment is an important contributing factor in falls among older adults, which is one of the leading causes of injury and injury-related death in this population. Visual impairment is also associated with greater disability among older adults, including poorer health-related quality of life, increased frailty and reduced postural stability. The majority of this evidence, however, is based on measures of central visual function, rather than peripheral visual function. As such, there is comparatively limited research on the associations between peripheral visual function, disability and falls, and even fewer studies involving older adults with specific diseases which affect peripheral visual function, the most common of which is glaucoma. Glaucoma is one of the leading causes of irreversible vision loss among older adults, affecting around 3 per cent of adults aged over 60 years. The condition is characterised by retinal nerve fibre loss, primarily affecting peripheral visual function. Importantly, the number of older adults with glaucomatous visual impairment is projected to increase as the ageing population grows. The first component of the thesis examined the cross-sectional association between glaucomatous visual impairment and health-related quality of life (Study 1a), functional status (Study 1b) and postural stability (Study 1c) among older adults. A cohort of 74 community-dwelling adults with glaucoma (mean age 74.2 ± 5.9 years) was recruited and completed a baseline assessment. A number of visual function measures was assessed, including central visual function (visual acuity and contrast sensitivity), motion sensitivity, retinal nerve fibre analysis and monocular and binocular visual field measures (monocular 24-2 and binocular integrated visual fields (IVF): IVF-60 and IVF-120). The analyses focused on the associations between the outcomes measures and severity and location of visual field loss, as this is the primary visual function affected by glaucoma. In Study 1a, we examined the association between visual field loss and health-related quality of life, measured by the Short Form 36-item Health Survey (SF-36). Greater binocular visual field loss, on both IVF measures, was associated with lower SF-36 physical component scores, adjusted for age and gender (Pearson's r =|0.32| to |0.36|, p<0.001). Furthermore, inferior visual field loss was more strongly associated with the SF-36 physical component than superior field loss. No association was found between visual field loss and SF-36 mental component scores. The association between visual field loss and functional status was examined in Study 1b. Functional status outcomes measures included a physical activity questionnaire (Physical Activity Scale for the Elderly, PASE), performance tests (six-minute walk test, timed up and go test and lower leg strength) and an overall functional status score. Significant, but weak, correlations were found between binocular visual field loss and PASE and overall functional status scores, adjusted for age and gender (Pearson's r =|0.24| to |0.33|, p<0.05). Greater inferior visual field loss, independent of superior visual field loss, was significantly associated with poorer physical performance results and lower overall functional status scores. In Study 1c, we examined the association between visual field loss and postural stability, using a swaymeter device which recorded body movement during four conditions: eyes open and closed, on a firm and foam surface. Greater binocular visual field loss was associated with increased postural sway, both on firm and foam surfaces, independent of age and gender (Pearson’s r =|0.44| to |0.46|, p <0.001). Furthermore, inferior visual field was a stronger contributor to postural stability, more so than the superior visual field, particularly on the foam condition with the eyes open. Greater visual field loss was associated with a reduction in the visual contribution to postural sway, which underlies the observed association with postural sway. The second component of the thesis examined the association between severity and location of visual field loss and falls during a 12-month longitudinal follow-up. The number of falls was assessed prospectively using monthly fall calendars. Of the 71 participants who successfully completed the follow up (mean age 73.9 ± 5.7 years), 44% reported one or more falls, and around 20% reported two or more falls. After adjusting for age and gender, every 10 points missed on the IVF-120 increased the rate of falls by 25% (rate ratio 1.25, 95% confidence interval 1.08 - 1.44) or every 5dB reduction in IVF-60 increased the rate of falls by 47% (rate ratio 1.47, 95% confidence interval 1.16 - 1.87). Inferior visual field loss was a significant predictor of falls, more so than superior field loss, highlighting the importance of the inferior visual field area in safe and efficient navigation. Further analyses indicated that postural stability, more so than functional status, may be a potential mediating factor in the relationship between visual field loss and falls. Future research is required to confirm this causal pathway. In addition, the use of topical beta-blocker medications was not associated with an increased rate of falls in this cohort, compared with the use of other topical anti-glaucoma medications. In summary, greater binocular visual field loss among older adults with glaucoma was associated with poorer health-related quality of life in the physical domain, reduced functional status, greater postural instability and higher rates of falling. When the location of visual field loss was examined, inferior visual field loss was consistently more strongly associated with these outcomes than superior visual field loss. Insights gained from this research improve our understanding of the association between glaucomatous visual field loss and disability, and its link with falls among older adults. The clinical implications of this research include the need to include visual field screening in falls risk assessments among older adults and to raise awareness of these findings to eye care practitioners and adults with glaucoma. The findings also assist in developing further research to examine strategies to reduce disability and prevent falls among older adults with glaucoma to promote healthy ageing and independence for these individuals.

Dealing with the problem of cybercrime

Lack of a universally accepted and comprehensive taxonomy of cybercrime seriously impedes international efforts to accurately identify, report and monitor cybercrime trends. There is, not surprisingly, a corresponding disconnect internationally on the cybercrime legislation front, a much more serious problem and one which the International Telecommunication Union (ITU) says requires „the urgent attention of all nations‟. Yet, and despite the existence of the Council of Europe Convention on Cybercrime, a proposal for a global cybercrime treaty was rejected by the United Nations (UN) as recently as April 2010. This paper presents a refined and comprehensive taxonomy of cybercrime and demonstrates its utility for widespread use. It analyses how the USA, the UK, Australia and the UAE align with the CoE Convention and finds that more needs to be done to achieve conformance. We conclude with an analysis of the approaches used in Australia, in Queensland, and in the UAE, in Abu Dhabi, to fight cybercrime and identify a number of shared problems.

The Simple Laws of Proportion

The Simple Laws of Proportion was shortlisted in the 2010 John Marsden Writing Prize for Young Australian Writers. It was subsequently published online by Express Media in December, 2010.

Mechanical properties of advanced tissue engineering scaffold architectures

In tissue engineering, porous scaffolds are used as a temporal support for tissue regeneration through cell adhesion, proliferation and differentiation. Besides applying a suitable material that is both biocompatible and biodegradable, the architectural design of the porous scaffold can be of essential for successful tissue regeneration. The architecture is of great influence on mechanical properties and transport properties of nutrients and metabolites1.

Poly(D,L-lactide)/hydroxyapatite composite tissue engineering scaffolds prepared by stereolithography

Hydroxyapatite (HAP) is a major component of bone and has osteoconductive and -inductive properties. It has been successfully applied as a substrate in bone tissue engineering, either with or without a biodegradable polymer such as polycaprolactone or polylactide. Recently, we have developed a stereolithography resin based on poly(D,L-lactide) (PDLLA) and a non-reactive diluent, that allows for the preparation of tissue engineering scaffolds with designed architectures. In this work, designed porous composite structures of PDLLA and HAP are prepared by stereolithography.

Network

Network has emerged from a contempory worldwide phenomenon, culturally manifested as a consequence of globalization and the knowledge economy. It is in this context that the internet revolution has prompted a radical re-ordering of social and institutional relations and the associated structures, processes and places which support them. Within the duality of virtual space and the augmentation of traditional notions of physical place, the organizational structures pose new challenges for the design professions. Technological developments increasingly permit communication anytime and anywhere, and provide the opportunity for both synchronous and asynchronous collaboration. The resultant ecology formed through the network enterprise has resulted in an often convolted and complex world wherein designers are forced to consider the relevance and meaning of this new context. The role of technology and that of space are thus interwined in the relation between the network and the individual workplace. This paper explores a way to inform the interior desgn process for contemporary workplace environments. It reports on both theoretical and practical outcomes through an Australia-wide case study of three collaborating, yet independent business entities. It further suggests the link between workplace design and successful business innovation being realized between partnering organizations in Great Britain. Evidence presented indicates that, for architects and interior designers, the scope of the problem has widened, the depth of knowledge required to provide solutions has increased, and the rules of engagement are required to change. The ontological and epistemological positions adopted in the study enabled the spatial dimensions to be examined from both within and beyond the confines of a traditional design only viewpoint. Importantly it highlights the significance of a trans-disiplinary collaboration in dealing with the multiple layers and complexity of the contemporary social and business world, from both a research and practice perspective.

Contribution of transmembrane domain V amino acids to β1l-adrenoceptor activity and affinity

There are two binding sites on the β1-adrenoceptor (AR), β1H and β1L corresponding to high and low affinity binding sites respectively, which can be activated to cause cardiostimulation (reviewed Kaumann and Molenaar, 2008). Some β-blockers that block β1AR and β2ARs can activate β1LARs at higher concentrations than those required to cause blockade. The β2AR does not form a corresponding low affinity binding site (Baker et al 2002) and therefore we postulated that heterologous amino acids are responsible for the formation of β1LAR. Our aim was to investigate whether heterologous amino acids of transmembrane domain V (TMDV) of β1AR and β2ARs contribute to β1LAR. β1ARs, β2ARs and mutant β1ARs containing all (β1(β2TMDV)AR) or single amino acids of TMDV of the β2AR were prepared and stably expressed in Chinese Hamster Ovary cells. Concentration-effect curves for cyclicAMP accumulation were carried out for (-)-CGP12177 or (-)-isoprenaline in the absence or presence of (-)-bupranolol. _______________________________________________________________________ (-)-CGP 12177 (-)-Bupranolol affinity (pKB) pEC50 vs (-)-CGP 12177 vs (-)-isoprenaline _______________________________________________________________________ β1AR 8.00 ± 0.11 (11) 7.23 ± 0.23 (5) 9.52 ± 0.28 (5) β2AR (high density) 9.24 ± 0.14 (5) 9.82 ± 0.52 (8) xPaulxxxxxxx β2AR (low density) no effect β1(β2TMV)AR 8.86 ± 0.10 (15) 8.06 ± 0.17 (8) 9.08 ± 0.22 (6) β1(V230I)AR 9.07 ± 0.07 (10) 7.64 ± 0.12 (8) 9.36 ± 0.28 (9) β1(R222Q)AR 8.09 ± 0.29 (6) 7.33 ± 0.23 (5) 9.36 ± 0.08 (6) β1(V230A)AR 7.59 ± 0.09 (6) 7.32 ± 0.24 (4) 8.62 ± 0.18 (5) _______________________________________________________________________ The potency of (-)-CGP12177 was higher at β2AR than at β1AR consistent with activation through a low affinity site at the β1AR (β1LAR) but not β2AR. The presence of V230 in β1AR accounted for the lower potency of (-)-CGP 12177. The affinity of (-)-bupranolol at β1AR and mutants was higher when determined with (-)-isoprenaline than with (-)-CGP 12177. The affinity of (-)-bupranolol determined against (-)-CGP 12177 was lower at β1AR compared to β2AR. The presence of V230 in β1AR accounted in part for the lower affinity. In conclusion V230 of the β1AR contributes in part to the low affinity binding site of β1AR. Baker JG, Hall IP, Hill SJ (2002). Pharmacological characterization of CGP12177 at the human β2-adrenoceptor. Br J Pharmacol 137, 400−408 Kaumann AJ, Molenaar P (2008) The low-affinity site of the β1-adrenoceptor and its relevance to cardiovascular pharmacology. Pharmacol Ther 118, 303-336

Textbooks and early childhood literacy

An historical and contemporary analysis of the political economy of textbooks, and affiliated new digital and print commodities, in early childhood and primary schooling.

The impact of contractor’s characteristics in gauging level satisfaction

The outcomes of the construction projects can be evaluated in numerous ways. One method is to measure the satisfaction of participants as represented by the differences between their expectations and perceptions. This measurement is used widely in construction as it promises benefits, such as the improvement of product delivery, and enhances services quality by identifying some necessary changes. Commonly satisfaction measurement is gauged by evaluating the level of client satisfaction of construction performance. The measurement of customer satisfaction on the other hand, is based on the quality of the end product. This evaluation is used to encourage contractors to improve their performance to a required level and to ensure that the projects are delivered as expected- in terms of time, budget and quality. Several studies of performance measurement have indicated that contractor performance is still not satisfactory, as the outcome delivered is not as required (because of cost overruns, time overruns or because it is generally unsatisfactory). This drawback may be due to the contractors’ lack of expertise, motivation and/or satisfaction. The measurement of performance based on contractor satisfaction levels is still new and very few studies have yet taken place in the construction industry. This paper examines how the characteristics of a contracting organisation – namely its experience in the industry, background, past performance, size of organisation and financial stability- may influence its satisfaction levels with regards to project performance. Previous literature reviews and interviews are used as research tools in the preliminary investigation. The outcome is expected to present a basic understanding of contractor satisfaction measurement and its potential for improving the performance of project outcomes.

Obituary - Rigid contact lenses

Scleral and corneal rigid lenses represented 100 per cent of the contact lens market immediately prior to the invention of soft lenses in the mid-1960s. In the United Kingdom today, rigid lenses comprise 2 per cent of all new lens fits. Low rates of rigid lens fitting are also apparent in 27 other countries which have recently been surveyed. Thus, the 1998 prediction of the author that rigid lenses – also referred to as ‘rigid gas permeable’ (RGP) lenses or ‘gas permeable’ (GP) lenses – would be obsolete by the year 2010 has essentially turned out to be correct. In this obituary, the author offers 10 reasons for the demise of rigid lens fitting: initial rigid lens discomfort; intractable rigid lens-induced corneal and lid pathology; extensive soft lens advertising; superior soft lens fitting logistics; lack of rigid lens training opportunities; redundancy of the rigid lens ‘problem solver’ function; improved soft toric and bifocal/varifocal lenses; limited uptake of orthokeratology; lack of investment in rigid lenses; and the emergence of aberration control soft lenses. Rigid lenses are now being fitted by a minority of practitioners with specialist skills/training. Certainly, rigid lenses can no longer be considered as a mainstream form of contact lens correction. May their dear souls (bulk properties) rest in peace.

Finding the remote: Immersive learning in an outback community

Real-world design education projects present particular challenges when in a place remote from and distinctively different to students’ familiar territory. The teaching challenge is to assist students to translate the skills they learn at university into an entirely new context, facilitating a project they will learn from, and the community will value. In 2008 QUT design and engineering students undertook a project called Linking Karumba for this remote Queensland town. They engaged with a landscape, climate and community dramatically different from their base in urban Brisbane, and in a fortnight produced locally responsive strategic planning options. The theoretical approach to this was twofold: they needed to make a rapid shift along a continuum from being “outsiders” towards becoming “insiders” (Relph 1976), and to create designs responsive to local distinctiveness (Cumberlidge and Musgrave 2007). This paper outlines Linking Karumba’s teaching strategy via an analogy with the “immersion” method in bilingual education. Three teaching methods were adopted. Firstly, the overall framework drew on Brockbank and McGill (1998), and Thomas’ (2006a) approaches to student reflective practice. Within this, Girot’s “Four Trace Concepts” (1999) inspired exercises for finding Karumba and moving toward insideness; and a program of community engagement sought immersion in local distinctiveness, and “conversation” between the differing forms of knowledge and capacities embedded within the community and students (Armstrong 1999, Thomas 2006). The responsiveness of the student work to the character of Karumba’s culture and environment indicated remarkable levels of immersion, and the community highly valued the project outcomes: four strategic planning options which attracted $830 000 in state government funding for implementation.

Spatial stimulus : Model making in the architectural design studio

This action research examines the enhancement of visual communication within the architectural design studio through physical model making. „It is through physical model making that designers explore their conceptual ideas and develop the creation and understanding of space,‟ (Salama & Wilkinson 2007:126). This research supplements Crowther‟s findings extending the understanding of visual dialogue to include physical models. „Architecture Design 8‟ is the final core design unit at QUT in the fourth year of the Bachelor of Design Architecture. At this stage it is essential that students have the ability to communicate their ideas in a comprehensive manner, relying on a combination of skill sets including drawing, physical model making, and computer modeling. Observations within this research indicates that students did not integrate the combination of the skill sets in the design process through the first half of the semester by focusing primarily on drawing and computer modeling. The challenge was to promote deeper learning through physical model making. This research addresses one of the primary reasons for the lack of physical model making, which was the limited assessment emphasis on the physical models. The unit was modified midway through the semester to better correlate the lecture theory with studio activities by incorporating a series of model making exercises conducted during the studio time. The outcome of each exercise was assessed. Tutors were surveyed regarding the model making activities and a focus group was conducted to obtain formal feedback from students. Students and tutors recognised the added value in communicating design ideas through physical forms and model making. The studio environment was invigorated by the enhanced learning outcomes of the students who participated in the model making exercises. The conclusions of this research will guide the structure of the upcoming iteration of the fourth year design unit.

How optometrists record corneal staining

Purpose: The aim of this study was to determine current approaches adopted by optometrists to the recording of corneal staining following fluorescein instillation. Methods: An anonymous ‘record-keeping task’ was sent to all 756 practitioners who are members of the Queensland Division of Optometrists Association Australia. This task comprised a form on which appeared a colour photograph depicting contact lens solution-induced corneal staining. Next to the photograph was an empty box, in which practitioners were asked to record their observations. Practitioners were also asked to indicate the level of severity of the condition at which treatment would be instigated. Results: Completed task forms were returned by 228 optometrists, representing a 30 per cent response rate. Ninety-two per cent of respondents offered a diagnosis. The most commonly used descriptive terms were ‘superficial punctate keratitis’ (36 per cent of respondents) and ‘punctate staining’ (29 per cent). The level of severity and location of corneal staining were noted by 69 and 68 per cent of respondents, respectively. A numerical grade was assigned by 44 per cent of respondents. Only three per cent nominated the grading scale used. The standard deviation of assigned grades was � 0.6. The condition was sketched by 35 per cent of respondents and two per cent stated that they would take a photograph of the eye. Ten per cent noted the eye in which the condition was being observed. Opinions of the level of severity at which treatment for corneal staining should be instigated varied considerably between practitioners, ranging from ‘any sign of corneal staining’ to ‘grade 4 staining’. Conclusion: Although most practitioners made a sensible note of the condition and properly recorded the location of corneal staining, serious deficiencies were evident regarding other aspects of record-keeping. Ongoing programs of professional optometric education should reinforce good practice in relation to clinical record-keeping.

An international survey of contact lens prescribing for presbyopia

Purpose: The aim was to determine world-wide patterns of fitting contact lenses for the correction of presbyopia. Methods: Up to 1,000 survey forms were sent to contact lens fitters in each of 38 countries between January and March every year over five consecutive years (2005 to 2009). Practitioners were asked to record data relating to the first 10 contact lens fittings or refittings performed after receiving the survey form. Results: Data were received relating to 16,680 presbyopic (age 45 years or older) and 84,202 pre-presbyopic (15 to 44 years) contact lens wearers. Females are over-represented in presbyopic versus pre-presbyopic groups, possibly reflecting a stronger desire for the cosmetic benefits of contact lenses among older women. The extent to which multifocal and monovision lenses are prescribed for presbyopes varies considerably among nations, ranging from 79 per cent of all soft lenses in Portugal to zero in Singapore. There appears to be significant under-prescribing of contact lenses for the correction of presbyopia, although for those who do receive such corrections, three times more multifocal lenses are fitted compared with monovision fittings. Presbyopic corrections are most frequently prescribed for full-time wear and monthly replacement. Conclusions: Despite apparent improvements in multifocal design and an increase in available multifocal options in recent years, practitioners are still under-prescribing with respect to the provision of appropriate contact lenses for the correction of presbyopia. Training of contact lens practitioners in presbyopic contact lens fitting should be accelerated and clinical and laboratory research in this field should be intensified to enhance the prospects of meeting the needs of presbyopic contact lens wearers more fully.

An enriched radial point interpolation method (e-RPIM) for analysis of crack tip fields

In this paper, an enriched radial point interpolation method (e-RPIM) is developed the for the determination of crack tip fields. In e-RPIM, the conventional RBF interpolation is novelly augmented by the suitable trigonometric basis functions to reflect the properties of stresses for the crack tip fields. The performance of the enriched RBF meshfree shape functions is firstly investigated to fit different surfaces. The surface fitting results have proven that, comparing with the conventional RBF shape function, the enriched RBF shape function has: (1) a similar accuracy to fit a polynomial surface; (2) a much better accuracy to fit a trigonometric surface; and (3) a similar interpolation stability without increase of the condition number of the RBF interpolation matrix. Therefore, it has proven that the enriched RBF shape function will not only possess all advantages of the conventional RBF shape function, but also can accurately reflect the properties of stresses for the crack tip fields. The system of equations for the crack analysis is then derived based on the enriched RBF meshfree shape function and the meshfree weak-form. Several problems of linear fracture mechanics are simulated using this newlydeveloped e-RPIM method. It has demonstrated that the present e-RPIM is very accurate and stable, and it has a good potential to develop a practical simulation tool for fracture mechanics problems.