329 resultados para Bubble Departure Diameter


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A study was conducted during 1997-99 at 2 sites in Sri Lanka (Rambukkana and Kurunegala) to investigate the responses of Swietenia macrophylla seedlings to wide, moderate and narrow openings of high to low shade conditions in a mature mixed mahogany plantations. Survival, stem growth and shoot phenology of seedlings were recorded monthly. Seedling survival a year after planting showed high mortality under high shaded gap (3-8% photosynthetically active radiation (PAR)). At 51 weeks after planting, final stem height and root collar diameter were highly significant under low shaded gaps. Increased number of shoots and shoot lenghts were observed under low shade (50-78% PAR). Increased flushing was seen in all shade regimes during the rainy period. This study illustrates that low shaded gap openings favour seeding survival, stem and shoot growth, and number of shoots. On the contrary, high shaded gaps reduce the growth of seedlings and therefore may be less attractive to shoot borers.

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Work zone safety studies have traditionally relied on historical crash records—an approach which is reactive in nature as it requires crashes to accumulate first before taking any preventive actions. However, detailed and accurate data on work zone crashes are often not available, as is the case for Australian road work zones. The lack of reliable safety records and the reactive nature of the crash-based safety analysis approach motivated this research to seek alternative and proactive measures of safety. Various surrogate measures of safety have been developed in the traffic safety literature including time to collision, time to accident, gap time, post encroachment time, required deceleration rate, proportion of stopping distances, lateral distance to departure, and time to departure. These measures express how close road-user(s) are from a potential crash by analysing their movement trajectories. A review of this fast-growing literature is presented in this paper from the viewpoint of applying the measures to untangle work zone safety issues. The review revealed that the use of the surrogate measures is very limited for analysing work zone safety, although numerous studies have used these measures for analysing safety in other parts of the road network, such as intersections and motorway ramps. There exist great opportunities for adopting this proactive safety assessment approach to transform work zone safety for both roadworkers and motorists.

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To See and Be Seen: Cinematic Constructions of Gender and Spectatorship in Contemporary Screen-Based Art addresses how gendered representation can be structured within visual art practice through a series of creative moving-image works. Using the aesthetic language of French New Wave cinema as its primary point of departure, this research project investigates how gendered representations are constructed by cinematic language. In doing this, it proposes latent possibilities present within the dominant gaze created by patriarchal relations of power. This project, in a series of creative works, demonstrates how the 'masculine' authorial gaze is learnt culturally, and by examining the gendered syntax of film, reveals how this can be recontextualised by the female artist.

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This presentation tells the story of an initiative in middle schooling at Kelvin Grove State College that begins in the Art studios, but reaches out to other disciplines and approaches, and to community and industry partners. It is inspired by the potential of 'future thinking' to become a compelling focus in contemporary art and design. Ethically it espouses a simple premise": every student in our classrooms now has a stake in creating livable, democratic and creative futures. Every student has the potential to be an active force in making that future. "100 Futures Now" is a project that envisages creative and imaginative students working in collaboration with artists and designers to visualize amazing futures and communicate their vision through art and design. "100 Futures Now" is one in a series of innovative curriculum initiatives at Kelvin Grove State College designed to build sustainable practice in arts education with the support of partners in industry and universities and with resident artists and designers. The model blends elements of art and design methodology to focus on the critical and creative thinking skills prioritised in ACARA and 21st century curriculum. The organisers are developing a sustainable model for working with resident artists that goes beyond a single arts intervention or extension/enrichment experience. In this model artists and designers are collaborators in the design of learning experiences that support future programs. This model also looks to transfer the benefits of residencies to the wider school community (in this case to middle schooling curriculum) and to teachers in other curriculum areas, and not exclusively to the immediate target group. In "100 Futures Now", story-making is the engine that powers the creative process. For this reason the program uses a series of imaginative scenarios, including those of speculative fiction and science, as departure points for inquiry, and applies the methodologies of arts and design practice to explore and express student story telling and story making. The story-making responses of student teams will naturally be expressed multimodally through visual art, design artifacts, installation, performance and digital works. The project’s focus on narratives and its modes of communication (performance/installation) are inspired by the work of experimental contemporary design practices and the speculative scenarios of U.K. based designers Anthony Dunne and Fiona Raby. Thanks to the support of an Arts Queensland Artist-in -Residence grant in 2014, resident artists and designers who work with a diversity of ideas and approaches ranging over science, bio-ethics, biodiversity, behavior and ethics, ambient sound, urbanism, food, and wearable design, will work with middle school students as catalysts for deeper thinking and creative action. All these rich fields for future speculation will become triggers for team inquiry into the deeper connections between the past, the present, and future challenges such as climate, waste, energy, sustainability and resilience. These imagined futures will form the platform for a critical, sustainability/design futures approach that will involve questioning assumptions and empowering students as agents rather than consumers of change.

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"Future Perfect" is a solo artist exhibition featuring a 9 channel video installation, which is comprised of looped computer animation projections. In the first room, the big one, there are nine projections of looped computer animations. Many of these look like representations of gallery spaces containing sculptures, including rotating interpenetrating discs, bouncing coloured coffins, and jostling cardboard cubes (the cubes are blank, then covered in drawings, then covered in photographic imagery). In one video, a man and a woman walk towards one another but never get together. In the second room, an animated video on a flatscreen suggests an origin story. The subtitles tell how, in Russia, my great-grandfather made a joke about Stalin's child bride that cost him his life. That one isn’t a loop; it has a beginning, middle, and end. Lying on the floor, in front of the video, are two slightly crumpled mural prints of photographs of the ocean. There's also a clear Perspex cloud shape on a wall. Viewers will see themselves reflected in it, as if it were a distant hovering mirage. The first room of the exhibition, where objects are set in perpetual motion, is about departure. The second room registers some sense of arrival. The future perfect implies looking back on something that hasn't happened yet; future and past are conflated and the present is somehow deferred. The future perfect combines anticipation and reflection, and it relates to my interest in combining 3-D animation with other mediums like drawing, painting, and shot video. In my work, the virtual and actual coexist in tension, just like experience and expectation in the future perfect.

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Herein are reported the synthesis of a conjugate of chitosan with L-leucine, the preparation of nanoparticles from both chitosan and the conjugate for use in pulmonary drug delivery, and the in vitro evaluation of toxicity and inflammatory effects of both the polymers and their nanoparticles on the bronchial epithelial cell line, BEAS-2B. The nanoparticles, successfully prepared both from chitosan and the conjugate, had a diameter in the range of 10−30 nm. The polymers and their nanoparticles were tested for their effects on cell viability by MTT assay, on trans-epithelial permeability by using sodium fluorescein as a fluid phase marker, and on IL-8 secretion by ELISA. The conjugate nanoparticles had a low overall toxicity (IC50 = 2 mg/mL following 48 h exposure; no induction of IL-8 release at 0.5 mg/mL concentration), suggesting that they may be safe for pulmonary drug delivery applications.

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Specialist palliative care is a prominent and expanding site of health service delivery, providing highly specialised care to people at the end of life. Its focus on the delivery of specialised life-enhancing care stands in contrast to biomedicine's general tendency towards life-prolonging intervention. This philosophical departure from curative or life-prolonging care means that transitioning patients can be problematic, with recent work suggesting a wide range of potential emotional, communication and relational difficulties for patients, families and health professionals. Yet, we know little about terminally ill patients' lived experiences of this complex transition. Here, through interviews with 40 inpatients in the last few weeks of life, we explore their embodied and relational experiences of the transition to inpatient care, including their accounts of an ethic of resilience in pre-palliative care and an ethic of acceptance as they move towards specialist palliative care. Exploring the relationship between resilience and acceptance reveals the opportunities, as well as the limitations, embedded in the normative constructs that inflect individual experience of this transition. This highlights a contradictory dynamic whereby participants' experiences were characterised by talk of initiating change, while also acquiescing to the terminal progression of their illness.

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What is ‘best practice’ when it comes to managing intellectual property rights in participatory media content? As commercial media and entertainment business models have increasingly come to rely upon the networked productivity of end-users (Banks and Humphreys 2008) this question has been framed as a problem of creative labour made all the more precarious by changing employment patterns and work cultures of knowledge-intensive societies and globalising economies (Banks, Gill and Taylor 2014). This paper considers how the problems of ownership are addressed in non-commercial, community-based arts and media contexts. Problems of labour are also manifest in these contexts (for example, reliance on volunteer labour and uncertain economic reward for creative excellence). Nonetheless, managing intellectual property rights in collaborative creative works that are created in community media and arts contexts is no less challenging or complex than in commercial contexts. This paper takes as its focus a particular participatory media practice known as ‘digital storytelling’. The digital storytelling method, formalised by the Centre for Digital Storytelling (CDS) from the mid-1990s, has been internationally adopted and adapted for use in an open-ended variety of community arts, education, health and allied services settings (Hartley and McWilliam 2009; Lambert 2013; Lundby 2008; Thumin 2012). It provides a useful point of departure for thinking about a range of collaborative media production practices that seek to address participation ‘gaps’ (Jenkins 2006). However the outputs of these activities, including digital stories, cannot be fully understood or accurately described as user-generated content. For this reason, digital storytelling is taken here to belong to a category of participatory media activity that has been described as ‘co-creative’ media (Spurgeon 2013) in order to improve understanding of the conditions of mediated and mediatized participation (Couldry 2008). This paper reports on a survey of the actual copyrighting practices of cultural institutions and community-based media arts practitioners that work with digital storytelling and similar participatory content creation methods. This survey finds that although there is a preference for Creative Commons licensing a great variety of approaches are taken to managing intellectual property rights in co-creative media. These range from the use of Creative Commons licences (for example, Lambert 2013, p.193) to retention of full copyrights by storytellers, to retention of certain rights by facilitating organisations (for example, broadcast rights by community radio stations and public service broadcasters), and a range of other shared rights arrangements between professional creative practitioners, the individual storytellers and communities with which they collaborate, media outlets, exhibitors and funders. This paper also considers how aesthetic and ethical considerations shape responses to questions of intellectual property rights in community media arts contexts. For example, embedded in the CDS digital storytelling method is ‘a critique of power and the numerous ways that rank is unconsciously expressed in engagements between classes, races and gender’ (Lambert 117). The CDS method privileges the interests of the storyteller and, through a transformative workshop process, aims to generate original individual stories that, in turn, reflect self-awareness of ‘how much the way we live is scripted by history, by social and cultural norms, by our own unique journey through a contradictory, and at times hostile, world’ (Lambert 118). Such a critical approach is characteristic of co-creative media practices. It extends to a heightened awareness of the risks of ‘story theft’ and the challenges of ownership and informs ideas of ‘best practice’ amongst creative practitioners, teaching artists and community media producers, along with commitments to achieving equitable solutions for all participants in co-creative media practice (for example, Lyons-Reid and Kuddell nd.). Yet, there is surprisingly little written about the challenges of managing intellectual property produced in co-creative media activities. A dialogic sense of ownership in stories has been identified as an indicator of successful digital storytelling practice (Hayes and Matusov 2005) and is helpful to grounding the more abstract claims of empowerment for social participation that are associated with co-creative methods. Contrary to the ‘change from below’ philosophy that underpins much thinking about co-creative media, however, discussions of intellectual property usually focus on how methods such as digital storytelling contribute to the formation of copyright law-compliant subjects, particularly when used in educational settings (for example, Ohler nd.). This also exposes the reliance of co-creative methods on the creative assets storytellers (rather than on the copyrighted materials of the media cultures of storytellers) as a pragmatic response to the constraints that intellectual property right laws impose on the entire category of participatory media. At the level of practical politics, it also becomes apparent that co-creative media practitioners and storytellers located in copyright jurisdictions governed by ‘fair use’ principles have much greater creative flexibility than those located in jurisdictions governed by ‘fair dealing’ principles.

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Background & Research Focus Managing knowledge for innovation and organisational benefit has been extensively investigated in studies of large firms (Smith, Collins & Clark, 2005; Zucker, et al., 2007) and to a large extent there is limited research into studies of small- and medium- sized enterprises (SMEs). There are some investigations in knowledge management research on SMEs, but what remains to be seen in particular is the question of where are the potential challenges for managing knowledge more effectively within these firms? Effective knowledge management (KM) processes and systems lead to improved performance in pursuing distinct capabilities that contribute to firm-level innovation (Nassim 2009; Zucker et al. 2007; Verona and Ravasi 2003). Managing internal and external knowledge in a way that links it closely to the innovation process can assist the creation and implementation of new products and services. KM is particularly important in knowledge intensive firms where the knowledge requirements are highly specialized, diverse and often emergent. However, to a large extent the KM processes of small firms that are often the source of new knowledge and an important element of the value networks of larger companies have not been closely studied. To address this gap which is of increasing importance with the growing number of small firms, we need to further investigate knowledge management processes and the ways that firms find, capture, apply and integrate knowledge from multiple sources for their innovation process. This study builds on the previous literature and applies existing frameworks and takes the process and activity view of knowledge management as a starting point of departure (see among others Kraaijenbrink, Wijnhoven & Groen, 2007; Enberg, Lindkvist, & Tell, 2006; Lu, Wang & Mao, 2007). In this paper, it is attempted to develop a better understanding of the challenges of knowledge management within the innovation process in small knowledge-oriented firms. The paper aims to explore knowledge management processes and practices in firms that are engaged in the new product/service development programs. Consistent with the exploratory character of the study, the research question is: How is knowledge integrated, sourced and recombined from internal and external sources for innovation and new product development? Research Method The research took an exploratory case study approach and developed a theoretical framework to investigate the knowledge situation of knowledge-intensive firms. Equipped with the conceptual foundation, the research adopted a multiple case study method investigating four diverse Australian knowledge-intensive firms from IT, biotechnology, nanotechnology and biochemistry industries. The multiple case study method allowed us to document in some depth the knowledge management experience of the theses firms. Case study data were collected through a review of company published data and semi-structured interviews with managers using an interview guide to ensure uniform coverage of the research themes. This interview guide was developed following development of the framework and a review of the methodologies and issues covered by similar studies in other countries and used some questions common to these studies. It was framed to gather data around knowledge management activity within the business, focusing on the identification, acquisition and utilisation of knowledge, but collecting a range of information about subject as well. The focus of the case studies was on the use of external and internal knowledge to support their knowledge intensive products and services. Key Findings Firstly a conceptual and strategic knowledge management framework has been developed. The knowledge determinants are related to the nature of knowledge, organisational context, and mechanism of the linkages between internal and external knowledge. Overall, a number of key observations derived from this study, which demonstrated the challenges of managing knowledge and how important KM is as a management tool for innovation process in knowledge-oriented firms. To summarise, findings suggest that knowledge management process in these firms is very much project focused and not embedded within the overall organisational routines and mainly based on ad hoc and informal processes. Our findings highlighted lack of formal knowledge management process within our sampled firms. This point to the need for more specialised capabilities in knowledge management for these firms. We observed a need for an effective knowledge transfer support system which is required to facilitate knowledge sharing and particularly capturing and transferring tacit knowledge from one team members to another. In sum, our findings indicate that building effective and adaptive IT systems to manage and share knowledge in the firm is one of the biggest challenges for these small firms. Also, there is little explicit strategy in small knowledge-intensive firms that is targeted at systematic KM either at the strategic or operational level. Therefore, a strategic approach to managing knowledge for innovation as well as leadership and management are essential to achieving effective KM. In particular, research findings demonstrate that gathering tacit knowledge, internal and external to the organization, and applying processes to ensure the availability of knowledge for innovation teams, drives down the risks and cost of innovation. KM activities and tools, such as KM systems, environmental scanning, benchmarking, intranets, firm-wide databases and communities of practice to acquire knowledge and to make it accessible, were elements of KM. Practical Implications The case study method that used in this study provides practical insight into the knowledge management process within Australian knowledge-intensive firms. It also provides useful lessons which can be used by other firms in managing the knowledge more effectively in the innovation process. The findings would be helpful for small firms that may be searching for a practical method for managing and integrating their specialised knowledge. Using the results of this exploratory study and to address the challenges of knowledge management, this study proposes five practices that are discussed in the paper for managing knowledge more efficiently to improve innovation: (1) Knowledge-based firms must be strategic in knowledge management processes for innovation, (2) Leadership and management should encourage various practices for knowledge management, (3) Capturing and sharing tacit knowledge is critical and should be managed, (4)Team knowledge integration practices should be developed, (5) Knowledge management and integration through communication networks, and technology systems should be encouraged and strengthen. In sum, the main managerial contribution of the paper is the recognition of knowledge determinants and processes, and their effects on the effective knowledge management within firm. This may serve as a useful benchmark in the strategic planning of the firm as it utilises new and specialised knowledge.

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PURPOSE The purpose of this study was to demonstrate the potential of near infrared (NIR) spectroscopy for characterizing the health and degenerative state of articular cartilage based on the components of the Mankin score. METHODS Three models of osteoarthritic degeneration induced in laboratory rats by anterior cruciate ligament (ACL) transection, meniscectomy (MSX), and intra-articular injection of monoiodoacetate (1 mg) (MIA) were used in this study. Degeneration was induced in the right knee joint; each model group consisted of 12 rats (N = 36). After 8 weeks, the animals were euthanized and knee joints were collected. A custom-made diffuse reflectance NIR probe of 5-mm diameter was placed on the tibial and femoral surfaces, and spectral data were acquired from each specimen in the wave number range of 4,000 to 12,500 cm(-1). After spectral data acquisition, the specimens were fixed and safranin O staining (SOS) was performed to assess disease severity based on the Mankin scoring system. Using multivariate statistical analysis, with spectral preprocessing and wavelength selection technique, the spectral data were then correlated to the structural integrity (SI), cellularity (CEL), and matrix staining (SOS) components of the Mankin score for all the samples tested. RESULTS ACL models showed mild cartilage degeneration, MSX models had moderate degeneration, and MIA models showed severe cartilage degenerative changes both morphologically and histologically. Our results reveal significant linear correlations between the NIR absorption spectra and SI (R(2) = 94.78%), CEL (R(2) = 88.03%), and SOS (R(2) = 96.39%) parameters of all samples in the models. In addition, clustering of the samples according to their level of degeneration, with respect to the Mankin components, was also observed. CONCLUSIONS NIR spectroscopic probing of articular cartilage can potentially provide critical information about the health of articular cartilage matrix in early and advanced stages of osteoarthritis (OA). CLINICAL RELEVANCE This rapid nondestructive method can facilitate clinical appraisal of articular cartilage integrity during arthroscopic surgery.

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Nitrogen is an important nutrient that can impact the quality of aquatic environments when present in high concentration. Even though low concentration levels of ammonium-nitrogen have been observed in laboratory studies in bioretention basins, poor removal or even the production of nitrate-nitrogen within the filter is often recorded in such studies. Ten Perspex biofilter columns of 94 mm (internal diameter) were packed with a filter layer, transition layer and a gravel layer. While the filter layer was packed to a height of 800 mm, transition and gravel layers were packed to a composite height of 220 mm and operated with simulated stormwater in the laboratory. The filter layer contained 8% organic material by weight. A free board of 350 mm provided detention storage and head to facilitate infiltration. The columns were operated with different antecedent dry days (0 d to 21 d) and constant inflow concentration at a feed rate of 100 mL/min. Samples were collected from the outflow at different time intervals, between 2 min and 150 min from the start of outflow, and were tested for nitrate-nitrogen and total organic carbon. Washoff of organic carbon from the filter layer was observed to occur for 30 min of outflow. This indicated washoff of organic carbon from the filter itself. At the same time, a very low concentration of nitrate-nitrogen was recorded at the beginning of the outflow, indicating the effective removal of nitrate-nitrogen. We conclude that the removal of nitrate-nitrogen is insignificant during the wetting phase of a rainfall event and the process of denitrification is more pronounced during the drying phase of a rainfall event. Thus intermittent wetting and drying is crucial for the removal of nitrate-nitrogen in bioretention basins.

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The successful establishment and growth of mixed-species forest plantations requires that complementary or facilitatory species be identified. This can be difficult in many tropical areas because the growth characteristics of endemic species are often unknown, particularly when grown at potentially higher densities in plantations than in natural forests. Here, we investigate whether wood density is a useful and readily accessible trait for choosing complementary species for mixed species plantations. Wood density represents the carbon investment per unit volume of stem with a trade-off generally found between fast (low wood density) and slow (high wood density) growing species. To do this, we use data collected from 18 highly diverse mixed species plantations (4–23 mostly native species) aged from 6 to 11 years at the time of data collection located on Leyte Island, Philippines. We found significant negative correlations between wood densities and the height of the most abundant species, as well as with measures of overall stand growth and tree diameter size distribution. Not only do species with denser woods have slower growth rates, but also mixed-species plantations with higher average wood density and higher stem density were also less productive, at least in these young plantations. Similarly, stands with a high diversity in wood densities were less productive. There is growing interest in making greater use of native multi-species mixtures in smallholder and community planting programs in the tropics, and our results show databases of wood density values may help improve their design. In the early development stages of plantations, canopy closure and rapid height growth are usually key silvicultural targets, and wood density values can predict the rapid height development of species. If plantations are being grown for the livelihood of small landholders then the best target is to choose some species with different wood densities. This allows an early harvest of low-wood density species for early income, and will also reduce competition for slower growing trees with higher wood densities for later income generation.

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Purpose: To determine the relative contributions of rods, cones and melanopsin to pupil responses in humans using temporal sinusoidal stimulation for light levels spanning the low mesopic to photopic range. Methods: A four-primary Ganzfeld photostimulator controlled flicker stimulations at seven light levels (-2.7 to 2 log cd/m2) and five frequencies (0.5 to 8Hz). Pupil diameter was measured using a high-resolution eyetracker. Three kinds of sinusoidal photoreceptor modulations were generated using silent substitution: 1) rod modulation, 2) cone modulation, and 3) combined rod and cone modulation in phase (Experiment 1) or phase shifted (Experiment 2) from a fixed rod phase. The melanopsin excitation was computed for each condition. A vector sum model was used to estimate the relative contribution of rods, cones and melanopsin to the pupil response. Results: From Experiment 1, the pupil frequency response peaked at 1Hz at two mesopic light levels for the three modulation conditions. Analyzing the rod-cone phase difference for the combined modulations (Experiment 2) identified a V-shaped response amplitude with a minimum between 135° and 180°. The pupil response phases increased as cone modulation phase increased. The pupil amplitude increased with increasing light level for cone and combined in-phase rod and cone modulation, but not for the rod modulation. Conclusions: These results demonstrate that cone- and rod-pathway contributions are more predominant than melanopsin contribution to the phasic pupil response. The combined rod, cone and melanopsin inputs to the phasic state of the pupil light reflex follow linear summation.

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Purpose There is a suggestion that the long wavelength-sensitive (LWS)-to-middle wavelength-sensitive (MWS) cone ratio in the retina is associated with myopia. The aim was to measure the LWS/MWS amplitude modulation ratio, an estimate of the LWS/MWS cone ratio, in young adult emmetropes and myopes. Methods Multifocal visual evoked potentials were measured when the LWS and MWS cone systems were excited separately using the method of silent substitution. The 30 young adult participants (22 to 33 years) included 10 emmetropes (mean [±SD] refraction, +0.3 [±0.4] diopters [D]) and 20 myopes (mean [±SD] refraction, -3.4 [±1.7] D). Results The LWS/MWS amplitude modulation ratios ranged from 0.56 to 1.80 in the central 3- to 13-degree diameter ring and from 0.94 to 1.91 in the peripheral 13- to 30-degree diameter ring. Within the central ring, the mean (±SD) ratios were 1.20 (±0.26) and 1.20 (±0.33) for the emmetropic and the myopic groups, respectively. For the peripheral ring, the mean (±SD) ratios were 1.48 (±0.27) and 1.30 (±0.27), respectively. There were no significant differences in the ratios between the emmetropic and myopic groups for either the central (p = 0.99) or peripheral (p = 0.08) rings. For the latter, more myopic refractive error was associated with lower LWS/MWS amplitude modulation ratio; the refraction explained 16% (p = 0.02) of variation in ratio. Conclusions The relationship between the LWS/MWS amplitude modulation ratios and refraction at 13 to 30 degrees indicates that a large longitudinal study of changes in refraction in persons with known cone ratio is required to determine if a low LWS/MWS cone ratio is associated with myopia development.