988 resultados para 141-863


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Increasing use of computerized systems in our daily lives creates new adversarial opportunities for which complex mechanisms are exploited to mend the rapid development of new attacks. Behavioral Biometrics appear as one of the promising response to these attacks. But it is a relatively new research area, specific frameworks for evaluation and development of behavioral biometrics solutions could not be found yet. In this paper we present a conception of a generic framework and runtime environment which will enable researchers to develop, evaluate and compare their behavioral biometrics solutions with repeatable experiments under the same conditions with the same data.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Graphene nanoribbon (GNR) with free edges demonstrates unique pre-existing edge energy and edge stress, leading to non-flat morphologies. Using molecular dynamics (MD) methods, we evaluated edge energies as well as edge stresses for four different edge types, including regular edges (armchair and zigzag), armchair edge terminated with hydrogen and reconstructed armchair. The results showed that compressive stress exists in the regular and hydrogen-terminated edges along the edge direction. In contrast, the reconstructed armchair edge is generally subject to tension. Furthermore, we also investigated shape transition between flat and rippled configurations of GNRs with different free edges. It was found that the pre-existing stress at free edges can greatly influence the initial energy state and the shape transition.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Titanium dioxide is one of the most basic materials in our daily life, which has emerged as an excellent photocatalyst material for environmental purification and photovoltaic material working in dye-sensitized solar cell. We present two types of TiO2 architectures which are constructed by plates and sheets, respectively, and both subunits are dominant with {001} facets. The photocatalytic degradation of methyl orange in UV/supported-TiO2 systems was investigated and the mechanism was discussed. The experimental results show that photocatalytic degradation rate is favoured by larger surface area. The sheet structure shows superior photocatalytic activity than plate structure. Moreover, the materials with sheet structure were also used to investigate the photovoltaic property. The power conversion efficiency is 7.57%, indicating the materials with this unique structure are excellent in photocatalytic and photovoltaic applications.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Carbon taxation governance is becoming increasingly popular, further evolving the polluter pays concept already well established in the built environment as a mechanism to controlling and licensing waste generation. This paper presents an explanation of property asset ‘regeneration reuse’ principles following deconstruction, which reduce waste generation associated with the process of demolition, construction and operation. An analysis is made of strategies in Australia and the United Kingdom, comparing jurisdiction targets pertaining to construction and demolition waste that encourage ‘regeneration reuse’. From examination of applicable Australian and United Kingdom legislation, strategic, fiscal and policy that influence on the 'regeneration reuse' of property assets, an evaluation to the variety of issues relevant to waste and resource management practices is reached. The paper concludes that a systematic evaluation framework to selecting building components and structures suitable for reuse after deconstruction must be considered in legislation.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In John Kallinicos Accountants Pty Ltd v Dundrenan Pty Ltd [2009] QDC 141 Irwin DCJ considered the nature of a party’s obligation under r 222 of the Uniform Civil Procedure Rules 1999 (Qld) (UCPR) to produce documents referred to in the parties’ pleadings, particulars or affidavits. The decision examined whether the approach in Belela Pty Ltd v Menzies Excavation Pty Ltd [2005] 2 QdR 230 in relation to disclosure of documents under UCPR r 214 also applied to production of documents under r 222.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We humans are complicated creatures. Despite remarkable intellect, a fearsome ability to push boundaries and superior survival mechanisms, we are at times our own worst enemy. Metabolic syndrome continues to be a premier health problem in developed, and now increasingly in undeveloped, nations. It is spreading across the planet like an infectious disease and is costing us millions. Metabolic disease remains an important focus both for medical research and for governments desperate to ease the burden on already over-taxed health systems. Unlike some previous worldwide health epidemics, obesity-related diseases will require more than a single, silver bullet. A simple vaccine or treatment cannot overcome a lack of education, awareness and in some cases sheer determination; the human element of these diseases. Undeniably, these ‘human elements’ also complicate our ability, as veterinarians, to effectively manage the growing incidence of equine obesity and metabolic disease...

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Ongoing problems exist with the commercial scale domestication of Penaeus monodon. One of the major issues, in terms of reproductive performance, is the low egg hatch rate of eggs from these captive bred prawns. The current study investigated the related issue of mating success. Time lapse video observations were conducted to compare the mating behaviour of pond-reared (domesticated) and wild-caught prawn P. monodon broodstock. Mating success of the pond-reared prawns was found to be low relative to wild-caught. It was determined that both male and female prawns contributed to this low mating rate suggesting both genders were impacted negatively by the domestication process. The causative factors for the low mating success are yet to be determined, however external physical abnormalities and lack of sexual maturity did not appear to play a role. The most notable behavioural difference between wild-caught and domesticated prawns was a reduced level of pursuit behaviour by domesticated males. This and other behavioural differences are discussed in relation to an increasing body of evidence that male prawns respond to sex pheromones produced by receptive females and that males detect these chemical signals in part, via their second antennal flagella. Accordingly we hypothesise that pond-reared (domesticated) females may have a reduced ability to produce or release sex pheromones and males, a reduced ability to detect them when compared to their wild-caught counterparts.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Neutrophils produce free radicals known as reactive oxygen species (ROS), which assist in the clearance of damaged host tissue. Tissue damage may occur during exercise due to muscle damage, thermal stress and ischaemia/reperfusion. When produced in excess, neutrophil-derived ROS may overwhelm the body's endogenous antioxidant defence mechanisms, and this can lead to oxidative stress. There is increasing evidence for links between oxidative stress and a variety of pathological disorders such as cardiovascular diseases, cancer, chronic inflammatory diseases and post-ischaemic organ injury. A small number of studies have investigated whether there is a link between neutrophil activation and oxidative stress during exercise. In this review, we have summarised the findings of these studies. Exercise promotes the release of neutrophils into the circulation, and some evidence suggests that neutrophils mobilised after exercise have an enhanced capacity to generate some forms of ROS when stimulated in vitro. Neutrophil activation during exercise may challenge endogenous antioxidant defence mechanisms, but does not appear to increase lipid markers of oxidative stress to any significant degree, at least in the circulation. Antioxidant supplements such as N-acetylcysteine are effective at attenuating increases in the capacity of neutrophils to generate ROS when stimulated in vitro, whereas vitamin E reduces tissue infiltration of neutrophils during exercise. Free radicals generated during intense exercise may lead to DNA damage in leukocytes, but it is unknown if this damage is the result of neutrophil activation. Exercise enhances the expression of inducible haem (heme)-oxygenase (HO-1) in neutrophils after exercise, however, it is uncertain whether oxidative stress is the stimulus for this response.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This work presents a collision avoidance approach based on omnidirectional cameras that does not require the estimation of range between two platforms to resolve a collision encounter. Our method achieves minimum separation between the two vehicles involved by maximising the view-angle given by the omnidirectional sensor. Only visual information is used to achieve avoidance under a bearing- only visual servoing approach. We provide theoretical problem formulation, as well as results from real flights using small quadrotors

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The host location behaviour of foraging caterpillars has received little attention, despite the wealth of theoretical and empirical studies that have been directed at this behavioural trait in adult Lepidoptera. Here, we study caterpillars of the moth Heliothis punctifera Walker (Lepidoptera: Noctuidae), which inhabits the arid inland desert areas of Australia. Caterpillars of this species consume many flowerheads before completing development and can be observed moving across the sand in search of new hosts. Consequently, if host location behaviour favours attraction to certain plant species, it might be expected to influence the distribution and abundance of caterpillars in the field. We present field data showing that H. punctifera caterpillars are unevenly distributed throughout mixed patches of two of its host species, with a higher abundance on Senecio gregorii F. Muell., the annual yellow top, compared to Myriocephalus stuartii (F. Muell. & Sond.) Benth., the poached egg daisy (both Asteraceae). Using laboratory studies, we test whether this distribution may, in part, be due to host location behaviour of caterpillars. Our results show that caterpillars exhibit a preference for locating S. gregorii in their pre- and post-contact foraging behaviour. In addition, our results provide evidence that feeding history plays a role in host location behaviour in this insect. We propose that key features of the desert environment and the ecology of H. punctifera would favour adaptations to host location behaviour by immatures.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The deposition of hyperthermal CH3 on diamond (001)-(2×1) surface at room temperature has been studied by means of molecular dynamics simulation using the many-body hydrocarbon potential. The energy threshold effect has been observed. That is, with fixed collision geometry, chemisorption can occur only when the incident energy of CH3 is above a critical value (Eth). Increasing the incident energy, dissociation of hydrogen atoms from the incident molecule was observed. The chemisorption probability of CH3 as a function of its incident energy was calculated and compared with that of C2H2. We found that below 10 eV, the chemisorption probability of C2H2 is much lower than that of CH3 on the same surface. The interesting thing is that it is even lower than that of CH3 on a hydrogen covered surface at the same impact energy. It indicates that the reactive CH3 molecule is the more important species than C2H2 in diamond synthesis at low energy, which is in good agreement with the experimental observation.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The mineral olshanskyite is one of many calcium borate minerals which has never been studied using vibrational spectroscopy. The mineral is unstable and decomposes upon exposure to an electron beam. This makes the elemental analysis using EDX techniques difficult. Both the Raman and infrared spectra show complexity due to the complexity of the structure. Intense Raman bands are found at 989, 1,003, 1,025 and 1,069 cm-1 with a shoulder at 961 cm-1 and are assigned to trigonal borate units. The Raman bands at 1,141, 1,206 and 1,365 cm-1 are assigned to OH in-plane bending of BOH units. A series of Raman bands are observed in the 2,900–3,621cm-1 spectral range and are assigned to the stretching vibrations of OH and water. This complexity is also reflected in the infrared spectra. Vibrational spectroscopy enables aspects of the structure of olshanskyite to be elucidated.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Synopsis and review of the Australian prison film Everynight...Everynight (Alkinos Tsilimidos, 1994). Includes cast and credits. An opening title states that Everynight… Everynight is a true story, but due to “legal implications”, the characters have been fictionalised. Another title dedicates the film to the memory of Christopher Dale Flannery, an infamous underworld figure known as ‘Mr Rent-a-Kill’ who spent time in H Division in the 1970s and 1980s. Originally from Melbourne, Flannery was a major figure in the Sydney ‘gang wars’ of 1984-85, dramatised in the television series Underbelly: A Tale of Two Cities (2009). He disappeared in mid-1985; there are several conflicting stories about his fate. The character of Bryant appears to have been based on Stan Taylor who had spent time in H Division with Flannery. Taylor was sentenced to life imprisonment without parole in 1988 for the 1986 bombing of police headquarters in Melbourne...

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Oceania has a relatively low level of crime prevalence yet in the smaller and under-developed PICs we have shown that transnational crime has become increasingly common. A risk contained but potentially dangerous if state failure or fragility undermines law enforcement capacities. We predict that as the pace of globalization quickens and the demand for raw materials and resources grows some parts of the Pacific will be prone to criminal enterprises run by both indigenous and foreign crime groups. Australia and New Zealand will remain attractors of illicit goods notably ATS but will in turn be source countries for diminishing fish stock such as beche de mere and abalone as well forest timber. Finally the role of states such as Australia and New Zealand in helping to maintain law enforcement capacities throughout the region will be crucial if organized crime in Oceania is to be kept in check while demand for illicit resources grow.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Purpose Virally mediated head and neck cancers (VMHNC) often present with nodal involvement and are highly radioresponsive, meaning that treatment plan adaptation during radiotherapy (RT) in a subset of patients is required. We sought to determine potential risk profiles and a corresponding adaptive treatment strategy for these patients. Methodology 121 patients with virally mediated, node positive nasopharyngeal (Epstein Barr Virus positive) or oropharyngeal (Human Papillomavirus positive) cancers, receiving curative intent RT were reviewed. The type, frequency and timing of adaptive interventions, including source-to-skin distance (SSD) corrections, re-scanning and re-planning, were evaluated. Patients were reviewed based on the maximum size of the dominant node to assess the need for plan adaptation. Results Forty-six patients (38%) required plan adaptation during treatment. The median fraction at which the adaptive intervention occurred was 26 for SSD corrections and 22 for re-planning CTs. A trend toward 3 risk profile groupings was discovered: 1) Low risk with minimal need (< 10%) for adaptive intervention (dominant pre-treatment nodal size of ≤ 35 mm), 2) Intermediate risk with possible need (< 20%) for adaptive intervention (dominant pre-treatment nodal size of 36 mm – 45 mm) and 3) High-risk with increased likelihood (> 50%) for adaptive intervention (dominant pre-treatment nodal size of ≥ 46 mm). Conclusion In this study, patients with VMHNC and a maximum dominant nodal size of > 46 mm were identified at a higher risk of requiring re-planning during a course of definitive RT. Findings will be tested in a future prospective adaptive RT study.