62 resultados para UV-written
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This paper formed the basis of a presentation to the Law Institute, Victoria, on 11 November 2002. The motivation for this paper has come from the recent writings of Laurence Boulle/. J. H. Wade4. and Gegorio Billikopf-Eucina5 • In addition to the acumen contained in the writings of the three authors above, this paper is laced with assertions and anecdotal evidence derived from the authors' experience in a variety of negotiation and mediation settings.
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One of the key debates within SLA research circles concerns grammar
- whether and hov to include it in second language (L2) instruction. 'Noninterventionist' approaches to language leaching, which centre on focus on meaning (FonM) , have been found to be neither economical nor expedient in terms of use of learners' classtime (Long & Robinson, 1998). This paper is a study of the effects oj direct grammatical instruction within a communicative context (Focus on Form - FonF) on the accuracy rate of the use of noun-adjective agreement in the written work of adult learners of Arabic. Learning the systems oj noun/adjective agreement in Arabic presents problems for beginners since. unlike languages such as English. Arabic needs to be modified for gender, number. definiteness and case. Through teaching material and methods, first-year university English speaking students of Arabic were directly exposed to morpho-syntactic inflections relevant to noun-adjective agreement. In post-tests over an extended period. instructed students showed a higher accuracy rate of some forms than their uninstructed colleagues. suggesting focusing on form is beneficial to the Arabic learner and does not need to interrupt the communicative flow in the classroom (Ellis et al. 2001).
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Introduction: There is wide variation in emergency nursing practice in terms of initial patient assessment and the interventions implemented in response to these patient assessment findings. It is hypothesised that written ED nursing practice standards will reduce variability in documentation standards related to initial patient assessment.
Aim: This study aimed to examine the effect of written ED nursing practice standards augmented by an in-service education programme on the documentation of the initial nursing assessment.
Method: A pre-test/post-test design was used. Initial patient assessment was assessed using the Emergency Department Observation Chart. All adult patients (>18 years) who presented with chest pain and who were triaged to the general adult cubicles were eligible for inclusion in the study. Random sampling was used to select the patients for the pre-test (n = 78) and post-test groups (n = 74).
Results: There was significant improvement in documentation of all aspects of symptom assessment except quality and historical variables: pre-hospital care, cardiac risk factors, and past medical history. Improvements in documentation of elements of primary survey assessment were variable. There were significant increases in documentation of respiratory effort, chest auscultation findings, capillary refill and conscious state. There was a significant 18.3% decrease in the frequency of documentation of respiratory rate and no significant changes in documentation of oxygen saturation, heart rate or blood pressure.
Conclusion: Written ED nursing practice standards were effective in improving the documentation of some elements of initial nursing assessment for patients with chest pain. Active implementation strategies are important to ensure effective uptake of written practice standards and the relationship between nursing documentation and actual clinical practice warrants further consideration using a naturalistic approach in real practice settings.
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The photocatalyst TiO2 with UV irradiation was used to degrade dyes in textile effluent in a flat-plate photoreactor. A test system was built with the reactor area of 1 x 0.3m2, UV light of six 36W-blacklight. TiO2 powder P25 with BET surface area 50±15m2/g, average primary particle size 21 nm, purity> 99.5% and content of 83.9% anatase and 16.1 % rutile was used as the photocatalyst. A number of dyes commonly present in dyeing wastewater were tested in this study. The different operating parameters, such as dosage of photocatalyst, the structure of the reactor, flow rates through the flat-plate reactor, UV radiation intensity and tilted angle of the reactor, were investigated. The results showed that the photocatalytic process could efficiently remove most of the colour contained in the dyeing wastewater. It was experimentally observed that first-order kinetics was adequate for characterising the process. The flow rate and the tilted angle had some influence on the film thickness of the fluid in the reactor and the empirical correlation between the film thickness of the fluid and these two parameters was developed. The photoreaction rate was mainly determined by the film thickness of the fluid on the reactor surface and the dosage of the photocatalyst. Optimum operating parameters of the system were found to be at the film thickness of about 1.4mm and a TiO2 dosage of 1 gIL. The higher the UV intensity, the faster the reaction rate was. The results of these experiments showed that this method has the great potential for colour removal from wastewater at commercial scale.
To overcome the common difficulty of separating the used TiO2 suspension after treatment precipitation followed with filtration was used in this study to determine the separation efficiencies. On the other hand, TiO2 in a small pillar shape was also studied for photocatalytic degradation of textile dye effluent. The pillar pellet was made in Oegussa Company, Germany ranging from 2.5 to 5.3mm long and with a diameter of 3.7mm. It was almost pure TiO2 (83.2% anatase and 16.8% rutile), with a S-content of <20 ppm and a CI content of the order of 0.1 wt. %. No further elements are present in contents above 0.05 wt.%. The TiO2 pillars were placed on the flat-plate reactor that was divided by the rectangular slots and irradiated under UV light when the treated solution went through the reactor. Four dyes and their mixtures were tested. The results showed that the photocatalytic process under this configuration efficiently remove the colour from textile dyeing effluent, and pillar shape TiO2 photocatalyst was not dissolved in water and very easy to be separated from solution, enabling it to be reused many times. The first-order kinetics was adequate for characterising the photocatalytic degradation process and the photocatalytic performance was comparable to TiO2 powder. It is believed that the TiO2 pellet would be a preferable form of photocatalyst in applications for textile effluent treatment process, and other wastewater treatment processes.
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Owing to their sessile nature, plants have evolved mechanisms to minimise the damaging effects of abiotic and biotic stresses. Attack by pathogenic fungi, viruses and bacterium is a major type of biotic stress. To resist infection, plants recognise invading pathogens and induce disease resistance through multiple signal transduction pathways. In addition, appropriate stimulation can cause plants to increase their resistance to future pathogen attack. We have found that exposure to non-lethal doses of UV-C (254 nm) renders a normally susceptible ecotype of Arabidopsis thaliana resistant to the biotrophic Oomycete pathogen Hyaloperonospora parasitica. The UV treatment induces an incompatible response in a dose-dependent fashion, and is still effective upon pathogen inoculation up to seven days after UV exposure. The degree of resistance diminishes with time but higher doses result in greater levels of resistance, even after seven days. Furthermore, the effect is systemic, occurring in parts of the plant that have not been irradiated. Incubation in the dark post?irradiation and prior to infection reduces the UV dose required to generate a specific level of pathogen resistance without affecting the duration of resistance. These observations, plus the inability of plants to photoreactivate UV photoproducts in the dark, strongly suggest that DNA damage induces the resistance phenotype. Currently, we are assessing the influence of DNA repair defects on UV-induced resistance, following the expression of a number of defence?related genes post-UV-C irradiation, and assessing the effect of UV in plant mutants deficient in specific signalling molecules involved in resistance.
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This paper describes the effect on the fading of dyed polyester fabrics in artificial sunlight, when the Ultra Violet (UV) component of the radiation was blocked by coating the fabric with zinc oxide nanoparticles, dispersed in an acrylic polymer. Zinc oxide is photoactive and generates superoxide and hydroxyl radicals (Reactive Oxygen Species; ROS) when irradiated with UV in the presence of oxygen and water. The results for the four dyes studied show that different dye chromophores interact differently with ROS. Selection of dyes with anti oxidant properties or addition of other anti oxidants may reduce the adverse effects of ROS
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Plant innate immunity to pathogenic microorganisms is activated in response to recognition of extracellular or intracellular pathogen molecules by transmembrane receptors or resistance proteins, respectively. The defense signaling pathways share components with those involved in plant responses to UV radiation, which can induce expression of plant genes important for pathogen resistance. Such intriguing links suggest that UV treatment might activate resistance to pathogens in normally susceptible host plants. Here, we demonstrate that pre-inoculative UV (254 nm) irradiation of Arabidopsis (Arabidopsis thaliana) susceptible to infection by the biotrophic oomycete Hyaloperonospora parasitica, the causative agent of downy mildew, induces dose- and time-dependent resistance to the pathogen detectable up to 7 d after UV exposure. Limiting repair of UV photoproducts by postirradiation incubation in the dark, or mutational inactivation of cyclobutane pyrimidine dimer photolyase, (6-4) photoproduct photolyase, or nucleotide excision repair increased the magnitude of UV-induced pathogen resistance. In the absence of treatment with 254-nm UV, plant nucleotide excision repair mutants also defective for cyclobutane pyrimidine dimer or (6-4) photoproduct photolyase displayed resistance to H. parasitica, partially attributable to short wavelength UV-B (280–320 nm) radiation emitted by incubator lights. These results indicate UV irradiation can initiate the development of resistance to H. parasitica in plants normally susceptible to the pathogen and point to a key role for UV-induced DNA damage. They also suggest UV treatment can circumvent the requirement for recognition of H. parasitica molecules by Arabidopsis proteins to activate an immune response.
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As the intensity of UV radiation increases every year, effective methods to block UV rays to protect human skin, plastics, timber and other polymer materials are urgently sought. Textiles serve as important materials for UV protection in many applications. The utilisation of nanoparticles to textile materials has been the object of several studies aimed at producing finished fabrics with different performances. This article reviews the recent advancement in the field of UV blocking textiles and fibers that are functionalised with nanostructured surface coatings. Different types of UV blocking agents are discussed and various examples of UV blocking textiles utilising ZnO and TiO2 are presented. Future challenges such as wash-fastness and photocatalysis are also discussed.
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The evaluation of new ventures often involves two key aspects of entrepreneurial business plans: how best to write them and how best to rate (evaluate) them. Ultimately the performance of the venture should be the definitive criterion of quality. Surprisingly, the writing, rating and performance effects of entrepreneurial business plans (EBPs) comprise three related but under researched areas. This article empirically tested principles for writing and rating entrepreneurial business plans to draw inferences on how to improve the private equity investment evaluation process. A simplified perspective of General Systems Theory guided our empirical investigation of the input and outcome of the VC investment decision. Our empirical investigation reveals that entrepreneurial business plans that comport with the writing principles from the literature improve a new venture's likelihood of success.
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ZnO, TiO2 and CeO2 are known as UV-shielding ceramic materials that have advantages over organic UV absorbers for their photo-stability and non-hazardous nature to human bodies. However, they normally cause low transparency in the visible-light range due to light scattering by large particles, which is undesirable for many transparent UV-blocking applications in cosmetic and plastic industries. Light-scattering efficiency of particles can be drastically reduced by decreasing the particle sizes down below 100 nm. This paper reviews recent investigation on the synthesis of ZnO and CeO2 nanoparticles by mechanochemical processing. The resulting particles had a significantly low degree of agglomeration, having mean particle sizes of ~ 25 nm and ~ 10 nm, respectively. The aqueous suspensions of the nanoparticles showed strong absorption in the UV-light range and high transmittance in the visible-light range. Mechanochemical processing offers the possibility of industrial-scale production of transparent UV-shielding ceramic particles for many applications.
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Many captive birds are kept in artificial lighting that is typically deficient in ultraviolet (UV) wavelengths. Most birds can perceive the range of light that humans see but also have an additional retinal cone type that is tuned to UV wavelengths. Consequently, artificial lighting may be detrimental as it might limit the functionality of their vision. We examined the preferences of European starlings, Sturnus vulgaris, for various artificial light environments. In our first experiment, groups of starlings showed a preference for environments that contained UV (UV+) over those where UV wavelengths had been removed (UV -). This preference was not affected by the sex of the individuals within the group or, as shown in a later experiment, by whether the birds had been previously housed in UV+ or UV - conditions. In contrast, individual starlings showed no preference for UV+ over UV - environments, although the power of our test was low. In a subsequent experiment, starling groups preferred the higher of two light intensities that were presented; however, equalizing the overall quantal flux between UV+ and UV - extinguished any preference for UV+ over UV -. The group preference for UV+ conditions in the first experiment may therefore have resulted from a preference for brighter conditions rather than a specific preference for UV. However, equalizing the quantal flux may not equalize perceived brightness, because it is not known how birds' visual systems weight input from each cone type. We conclude that, for nonbreeding, group-housed captive starlings, there is no positive evidence of a preference for the presence of UV as a specific wavelength. (C) 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.