905 resultados para dark-germination.


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Embryogenic callus was initiated by culturing in vitro taro corm slices on agar-solidified half-strength MS medium containing 2.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) for 20 days followed by transfer to 1.0 mg/L thidiazuron (TDZ). Callus was subsequently proliferated on solid medium containing 1.0 mg/L TDZ, 0.5 mg/L 2,4- D and 800 mg/L glutamine before transfer to liquid medium containing the same components but with reduced glutamine (100 mg/L). After 3 months in liquid culture on an orbital shaker, cytoplasmically dense cell aggregates began to form. Somatic embryogenesis was induced by plating suspension cells onto solid media containing reduced levels of hormones (0.1 mg/L TDZ, 0.05 mg/L 2,4-D), high concentrations of sucrose (40–50 g/L) and biotin (1.0 mg/L). Embryo maturation and germination was then induced on media containing 0.05 mg/L benzyladenine (BA) and 0.1 mg/L indole-3-acetic acid (IAA). Histological studies of the developing embryos revealed the presence of typical shoot and root poles suggesting that these structures were true somatic embryos. The rate of somatic embryos formation was 500–3,000 per mL settledcell volume while approximately 60% of the embryos regenerated into plants.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Within the Australian wet tropics bioregion, only 900 000 hectares of once continuous rainforest habitat between Townsville and Cooktown now remains. While on the Atherton Tableland, only 4% of the rainforest that once occurred there remains today with remnant vegetation now forming a matrix of rainforest dispersed within agricultural land (sugarcane, banana, orchard crops, townships and pastoral land). Some biologists have suggested that remnants often support both faunal and floral communities that differ significantly from remaining continuous forest. Australian tropical forests possess a relatively high diversity of native small mammal species particularly rodents, which unlike larger mammalian and avian frugivores elsewhere, have been shown to be resilient to the effects of fragmentation, patch isolation and reduction in patch size. While small mammals often become the dominant mammalian frugivores, in terms of their relative abundance, the relationship that exists between habitat diversity and structure, and the impacts of small mammal foraging within fragmented habitat patches in Australia, is still poorly understood. The relationship between foraging behaviour and demography of two small mammal species, Rattus fuscipes and Melomys cervinipes, and food resources in fragmented rainforest sites, were investigated in the current study. Population densities of both species were strongly related with overall density of seed resources in all rainforest fragments. The distribution of both mammal species however, was found to be independent of the distribution of seed resources. Seed utilisation trials indicated that M.cervinipes and R.fuscipes had less impact on seed resources (extent of seed harvesting) than did other rainforest frugivores. Experimental feeding trials demonstrated that in 85% of fruit species tested, rodent feeding increased seed germination by a factor of 3.5 suggesting that in Australian tropical rainforest remnants, small mammals may play a significant role in enhancing germination of large seeded fruits. This study has emphasised the role of small mammals in tropical rainforest systems in north eastern Australia, in particular, the role that they play within isolated forest fragments where larger frugivorous species may be absent.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Sydney Harbour Bridge provides an imaginative space that is revisited by Australian writers in particular ways. In this space novelists, poets, and cultural historians negotiate questions of emotional and psychological transformation as well as reflect on social and environmental change in the city of Sydney. The writerly tensions that mark these accounts often alter, or query, representations of the Bridge as a symbol of material progress and demonstrate a complex creative engagement with the Bridge. This discussion of ‘the Bridge’ focuses on the work of four authors, Eleanor Dark, P.R. Stephensen, Peter Carey and Vicki Hastrich and includes a range of other fictional and non-fictional accounts of ‘Bridge-writing.’ The ideas proffered are framed by a theorising of space, especially referencing the work of Michel de Certeau, whose writing on the spatial ambiguity of a bridge is important to the examination of the diverse ways in which Australian writers have engaged with the imaginative potential and almost mythic resonance of the Sydney Harbour Bridge.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In the late 1990s New Zealand fashion gained some international recognition for its dark edginess and intellectual connection due to its colonial past (Molloy, 2004). In the years since, this momentum seems to have dissipated as local fashion companies have followed a global trend towards inexpensive off shore manufacturing. The transfer of the making of garments to overseas workers appears to have resulted in a local fashion scene where many garments look the same in style, colour, cut and fit. The excitement of the past, where the majority of fashion designers established their own individuality through the cut and shape of the garments that they produced, may have been inadvertently lost. Consequently a sustainable New Zealand fashion and manufacturing industry, with design integrity, seems further out of reach. The first question posed by this research project is, ‘can the design and manufacture of a fashion garment, bearing in mind certain economic and practical restrictions at its inception, result in the development of a distinctive ‘look’ or ‘handwriting’?’ Second, through development of a collection of prototypes, can potential garments be created to be sustainably manufactured in New Zealand?

Relevância:

10.00% 10.00%

Publicador:

Resumo:

There is a need in industry for a commodity polyethylene film with controllable degradation properties that will degrade in an environmentally neutral way, for applications such as shopping bags and packaging film. Additives such as starch have been shown to accelerate the degradation of plastic films, however control of degradation is required so that the film will retain its mechanical properties during storage and use, and then degrade when no longer required. By the addition of a photocatalyst it is hoped that polymer film will breakdown with exposure to sunlight. Furthermore, it is desired that the polymer film will degrade in the dark, after a short initial exposure to sunlight. Research has been undertaken into the photo- and thermo-oxidative degradation processes of 25 ìm thick LLDPE (linear low density polyethylene) film containing titania from different manufacturers. Films were aged in a suntest or in an oven at 50 °C, and the oxidation product formation was followed using IR spectroscopy. Degussa P25, Kronos 1002, and various organic-modified and doped titanias of the types Satchleben Hombitan and Hunstsman Tioxide incorporated into LLDPE films were assessed for photoactivity. Degussa P25 was found to be the most photoactive with UVA and UVC exposure. Surface modification of titania was found to reduce photoactivity. Crystal phase is thought to be among the most important factors when assessing the photoactivity of titania as a photocatalyst for degradation. Pre-irradiation with UVA or UVC for 24 hours of the film containing 3% Degussa P25 titania prior to aging in an oven resulted in embrittlement in ca. 200 days. The multivariate data analysis technique PCA (principal component analysis) was used as an exploratory tool to investigate the IR spectral data. Oxidation products formed in similar relative concentrations across all samples, confirming that titania was catalysing the oxidation of the LLDPE film without changing the oxidation pathway. PCA was also employed to compare rates of degradation in different films. PCA enabled the discovery of water vapour trapped inside cavities formed by oxidation by titania particles. Imaging ATR/FTIR spectroscopy with high lateral resolution was used in a novel experiment to examine the heterogeneous nature of oxidation of a model polymer compound caused by the presence of titania particles. A model polymer containing Degussa P25 titania was solvent cast onto the internal reflection element of the imaging ATR/FTIR and the oxidation under UVC was examined over time. Sensitisation of 5 ìm domains by titania resulted in areas of relatively high oxidation product concentration. The suitability of transmission IR with a synchrotron light source to the study of polymer film oxidation was assessed as the Australian Synchrotron in Melbourne, Australia. Challenges such as interference fringes and poor signal-to-noise ratio need to be addressed before this can become a routine technique.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

At the centre of this research is an ethnographic study that saw the researcher embedded within the fabric of inner city life to better understand what characteristics of user activity and interaction could be enhanced by technology. The initial research indicated that the experience of traversing the city after dark unified an otherwise divergent user group through a shared concern for personal safety. Managing this fear and danger represented an important user need. We found that mobile social networking systems are not only integral for bringing people together, they can help in the process of users safely dispersing as well. We conclude, however, that at a time when the average iPhone staggers under the weight of a plethora of apps that do everything from acting as a carpenter’s level to a pregnancy predictor, we consider the potential for the functionality of a personal safety device to be embodied within a stand alone artifact.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Within a surveillance video, occlusions are commonplace, and accurately resolving these occlusions is key when seeking to accurately track objects. The challenge of accurately segmenting objects is further complicated by the fact that within many real-world surveillance environments, the objects appear very similar. For example, footage of pedestrians in a city environment will consist of many people wearing dark suits. In this paper, we propose a novel technique to segment groups and resolve occlusions using optical flow discontinuities. We demonstrate that the ratio of continuous to discontinuous pixels within a region can be used to locate the overlapping edges, and incorporate this into an object tracking framework. Results on a portion of the ETISEO database show that the proposed algorithm results in improved tracking performance overall, and improved tracking within occlusions.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Northern Hemisphere slumbers, dreaming that – one day – it is going to split up its empire, before the seas boil and the towers collapse. During this same dark night, Australia is wide awake, chirpy as a Canadian, strapping as a Bondi blonde, having an election...

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Purpose: Businesses cannot rely on their customers to always do the right thing. To help researchers and service providers better understand the dark (and light) side of customer behavior, this study aims to aggregate and investigate perceptions of consumer ethics from young consumers on five continents. The study seeks to present a profile of consumer behavioral norms, how ethical inclinations have evolved over time, and country differences. ---------- Design/methodology/approach: Data were collected from ten countries across five continents between 1997 and 2007. A self-administered questionnaire containing 14 consumer scenarios asked respondents to rate acceptability of questionable consumer actions. ---------- Findings: Overall, consumers found four of the 14 questionable consumer actions acceptable. Illegal activities were mostly viewed as unethical, while some legal actions that were against company policy were viewed less harshly. Differences across continents emerged, with Europeans being the least critical, while Asians and Africans shared duties as most critical of consumer actions. Over time, consumers have become less tolerant of questionable behaviors. ---------- Practical implications: Service providers should use the findings of this study to better understand the service customer. Knowing what customers in general believe is ethical or unethical can help service designers focus on the aspects of the technology or design most vulnerable to customer deviance. ---------- Multinationals already know they must adapt their business practices to the market in which they are operating, but they must also adapt their expectations as to the behavior of the corresponding consumer base. Originality/value: This investigation into consumer ethics helps businesses understand what their customer base believes is the right thing in their role as customer. This is a large-scale study of consumer ethics including 3,739 respondents on five continents offering an evolving view of the ethical inclinations of young consumers.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In Powers of Horror, Julia Kristeva writes about lost children. These are what she calls “dejects,” who, in the psychodrama of subject formation, fail to fully absent the body of the mother, to accept the Law of the Father and the Symbolic, and subsequently to establish “clear boundaries which constitute the object-world for normal subjects.” Dejects are “strays” looking for a place to belong, a place that is bound up with the Imaginary mother of the pre-Oedipal period. Kristeva’s sketch of the deject as one who is unable to negotiate a proper path to the Symbolicis useful to a reading of Hartnett’s Of A Boy (2002),a novel that also deals with lost children and imaginary mothers. However, in its portrayal of children who are doomed to never achieve adulthood, Of A Boy enacts a haunting retrieval of the pre-Oedipal from the dark side of phallocentric representation, privileging the semiotic (Kristeva’s concept) and the maternal as necessary disruptive checks on a patriarchal Symbolic Order.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

NOBEL prize-winning British writer Harold Pinter is best known for his social commentaries and for dark, sometimes violent "comedies of menace" that capture the cruelty at the heart of human relationships. It has been a while since a Pinter play was on the Brisbane stage, and it is exciting to see one of his lesser known early works, Betrayal, as part of Queensland Theatre Company's session. Betrayal moves backwards from a potentially scandalous moment. In a pub one night, Emma tells Jerry that his best friend Robert is divorcing her. Robert has been unfaithful. And, what's more, Robert now knows about their lengthy affair. What follows is a series of scenes that look back at the stages of that affair and the secrets that have lain unspoken at the heart of their comfortable middle-class lives for so long. Betrayal is characterised by the sparsity of action and language, dark humour, and sudden outbreaks of seemingly excessive cruelty that are a trademark of Pinter's writing for the theatre.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The focus of this paper is preparing research for dissemination by mainstream print, broadcast, and online media. While the rise of the blogosphere and social media is proving an effective way of reaching niche audiences, my own research reached such an audience through traditional media. The first major study of Australian horror cinema, my PhD thesis A Dark New World: Anatomy of Australian Horror Films, generated strong interest from horror movie fans, film scholars, and filmmakers. I worked closely with the Queensland University of Technology’s (QUT) public relations unit to write two separate media releases circulated on October 13, 2008 and October 14, 2009. This chapter reflects upon the process of working with the media and provides tips for reaching audiences, particularly in terms of strategically planning outcomes. It delves into the background of my study which would later influence my approach to the media, the process of drafting media releases, and key outcomes and benefits from popularising research. A key lesson from this experience is that redeveloping research for the media requires a sharp writing style, letting go of academic justification, catchy quotes, and an ability to distil complex details into easy-to-understand concepts. Although my study received strong media coverage, and I have since become a media commentator, my experiences also revealed a number of pitfalls that are likely to arise for other researchers keen on targeting media coverage.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Previous research has suggested that perceptual-motor difficulties may account for obese children's lower motor competence; however, specific evidence is currently lacking. Therefore, this study examined the effect of altered visual conditions on spatiotemporal and kinematic gait parameters in obese versus normal-weight children. Thirty-two obese and normal-weight children (11.2 ± 1.5 years) walked barefoot on an instrumented walkway at constant self-selected speed during LIGHT and DARK conditions. Three-dimensional motion analysis was performed to calculate spatiotemporal parameters, as well as sagittal trunk segment and lower extremity joint angles at heel-strike and toe-off. Self-selected speed did not significantly differ between groups. In the DARK condition, all participants walked at a significantly slower speed, decreased stride length, and increased stride width. Without normal vision, obese children had a more pronounced increase in relative double support time compared to the normal-weight group, resulting in a significantly greater percentage of the gait cycle spent in stance. Walking in the DARK, both groups showed greater forward tilt of the trunk and restricted hip movement. All participants had increased knee flexion at heel-strike, as well as decreased knee extension and ankle plantarflexion at toe-off in the DARK condition. The removal of normal vision affected obese children's temporal gait pattern to a larger extent than that of normal-weight peers. Results suggest an increased dependency on vision in obese children to control locomotion. Next to the mechanical problem of moving excess mass, a different coupling between perception and action appears to be governing obese children's motor coordination and control.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Daylighting in tropical and sub-tropical climates presents a unique challenge that is generally not well understood by designers. In a sub-tropical region such as Brisbane, Australia the majority of the year comprises of sunny clear skies with few overcast days and as a consequence windows can easily become sources of overheating and glare. The main strategy in dealing with this issue is extensive shading on windows. However, this in turn prevents daylight penetration into buildings often causing an interior to appear gloomy and dark even though there is more than sufficient daylight available. As a result electric lighting is the main source of light, even during the day. Innovative daylight devices which redirect light from windows offer a potential solution to this issue. These devices can potentially improve daylighting in buildings by increasing the illumination within the environment decreasing the high contrast between the window and work regions and deflecting potentially glare causing sunlight away from the observer. However, the performance of such innovative daylighting devices are generally quantified under overcast skies (i.e. daylight factors) or skies without sun, which are typical of European climates and are misleading when considering these devices for tropical or sub-tropical climates. This study sought to compare four innovative window daylighting devices in RADIANCE; light shelves, laser cut panels, micro-light guides and light redirecting blinds. These devices were simulated in RADIANCE under sub-tropical skies (for Brisbane) within the test case of a typical CBD office space. For each device the quantity of light redirected and its distribution within the space was used as the basis for comparison. In addition, glare analysis on each device was conducted using Weinold and Christoffersons evalglare. The analysis was conducted for selected hours for a day in each season. The majority of buildings that humans will occupy in their lifetime are already constructed, and extensive remodelling of most of these buildings is unlikely. Therefore the most effective way to improve daylighting in the near future will be through the alteration existing window spaces. Thus it will be important to understand the performance of daylighting systems with respect to the climate it is to be used in. This type of analysis is important to determine the applicability of a daylighting strategy so that designers can achieve energy efficiency as well the health benefits of natural daylight.