96 resultados para Stone, Crushed.

em Queensland University of Technology - ePrints Archive


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Protecting slow sand filters (SSFs) from high-turbidity waters by pretreatment using pebble matrix filtration (PMF) has previously been studied in the laboratory at University College London, followed by pilot field trials in Papua New Guinea and Serbia. The first full-scale PMF plant was completed at a water-treatment plant in Sri Lanka in 2008, and during its construction, problems were encountered in sourcing the required size of pebbles and sand as filter media. Because sourcing of uniform-sized pebbles may be problematic in many countries, the performance of alternative media has been investigated for the sustainability of the PMF system. Hand-formed clay balls made at a 100-yearold brick factory in the United Kingdom appear to have satisfied the role of pebbles, and a laboratory filter column was operated by using these clay balls together with recycled crushed glass as an alternative to sand media in the PMF. Results showed that in countries where uniform-sized pebbles are difficult to obtain, clay balls are an effective and feasible alternative to natural pebbles. Also, recycled crushed glass performed as well as or better than silica sand as an alternative fine media in the clarification process, although cleaning by drainage was more effective with sand media. In the tested filtration velocity range of ð0:72–1:33Þ m=h and inlet turbidity range of (78–589) NTU, both sand and glass produced above 95% removal efficiencies. The head loss development during clogging was about 30% higher in sand than in glass media.

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Purpose. To evaluate the influence of co-administered vehicles on in vitro dissolution in simulated gastric fluid of crushed immediate release tablets as an indicator for potential drug bioavailability compromise. Methods. Release and dissolution of crushed amlodipine, atenolol, carbamazepine and warfarin tablets were tested with six foods and drinks that are frequently used in the clinical setting as mixers for crushed medications (water, orange juice, honey, yoghurt, strawberry jam and water thickened with Easythick powder) in comparison to whole tablets. Five commercial thickening agents (Easythick Advanced, Janbak F, Karicare, Nutilis, Viscaid) at three thickness levels were tested for their effect on the dissolution of crushed atenolol tablets. Results. Atenolol dissolution was unaffected by mixing crushed tablets with thin fluids or food mixers in comparison to whole tablets or crushed tablets in water, but amlodipine was delayed by mixing with jam. Mixing crushed warfarin and carbamazepine tablets with honey, jam or yoghurt caused them to resemble the slow dissolution of whole tablets rather than the faster dissolution of crushed tablets in water or orange juice. Crushing and mixing any of the four medications with thickened water caused a significant delay in dissolution. When tested with atenolol, all types of thickening agents at the greatest thickness significantly restricted dissolution, and products that are primarily based on xanthan gum also delayed dissolution at the intermediate thickness level. Conclusions. Dissolution testing, while simplistic, is a widely used and accepted method for comparing drug release from different formulations as an indicator for in vivo bioavailability. Thickened fluids have the potential to retard drug dissolution when used at the thickest levels. These findings highlight potential clinical implications of the addition of these agents to medications for the purpose of dose delivery and indicate that further investigation of thickened fluids and their potential to influence therapeutic outcomes is warranted.

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Solid medications are often crushed and mixed with food or thickened water to aid drug delivery for those who cannot or prefer not to swallow whole tablets or capsules. Dysphagic patients have the added problem of being unable to safely swallow thin fluids so water thickened with polysaccharides is used to deliver crushed medications and ensure safe swallowing. It is postulated that these polysaccharide systems may restrict drug release by reducing the diffusion of the drug into gastric fluids. METHODS By using a vertical diffusion cell separated with a synthetic membrane, the diffusion of a model drug (atenolol) was studied from a donor system containing the drug dispersed into thickened water with xanthan gum (concentration range from 0.005%-2.2%) into a receptor system containing simulated gastric fluid (SGF) at 37°C. The amount of drug transferred was measured over 8 hours and diffusion coefficients estimated using the Higuchi model approach. RESULTS Atenolol diffusion decreased with increasing xanthan gum concentration up to 1.0%, above which diffusion remained around 300 μ2s-1. The rheological measurements captured the influence of the structure and conformation of the polysaccharide in water on the movement and availability of the drug in SGF. DISCUSSION Dose form administration for dysphagic patients’ needs special attention from general practitioners, pharmacist and patients. Improving drug release of crushed tablets from thickening agents requires a reduction in the diffusion pathway (e.g. by decreasing drop size radius). This approach could make the drug available in SGF in a short time without compromising the mechanical aspects of thickening agents that guarantee safe swallowing.

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Dysphagia, often associated with conditions such as stroke, Parkinson’s disease, multiple sclerosis, and dementia, causes patients to have difficulty with swallowing food and/or liquids. These patients require their fluids to be thickened using gum-based thickening powders in order to facilitate safe swallowing. These thickened fluids are also used as a vehicle for delivery of crushed medicines. Our in vitro measurements suggest that thickened fluids can delay and reduce the dissolution of a number of medications. This study was conducted to assess the impact of the use of thickened fluids on the clinical pharmacokinetics of oral paracetamol. METHODS 20 Healthy volunteers were administered a single oral dose (1g) of paracetamol as either whole tablets, crushed with water, crushed with semi-solid jam, or crushed with thickened fluid according to a randomised, crossover design. Saliva samples were collected periodically over 8 hr and paracetamol concentration analysed by HPLC-UV. Non-compartmental pharmacokinetic analysis was conducted using Winnonlin®. RESULTS The mean peak concentration (Cmax) of paracetamol ranged between 5.62 – 8.00 μg/mL. Comparison between the crushed paracetamol with thickened water (Level 900) and other treatment options (whole, crushed with water, and crushed with jam) showed there was a significant difference in Cmax at 90% CI (p < 0.05). Also, whole tablet had a significant difference in Cmax between crushed with water and crushed with jam. There was no significant difference in AUC irrespective of the treatment. DISCUSSION The use of thickened water resulted in alteration in the absorption kinetics of paracetamol. Given this interaction, co-administration with thickened fluids may have important clinical implications for medications with a narrow therapeutic index.

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Informed by Kristeva's formulation of affect and Winnicott's Holding Environment, this practice-led visual art project is an exploration into how sensitivity to the physical sensation of trembling can sustain a creative practice. Building upon this is a further enquiry into what the significance of the affective experience of trembling is for an ethics of affect in contemporary art. I have done this through object and video-based installations informed by my own experience of trembling. This has been further informed by the work of artists like Louise Bourgeois, Dennis Del Favero and Willie Doherty. The creative outcomes contribute to the discourse around ethical responses to affect by extending and developing on the works of these artists.

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Stone Baby: An Exploration of Affect and Trauma in Visual Art was held at the Block, QUT Creative Industries Precinct on August 27-28, 2014. At the conclusion of my Masters project, this exhibition was a showcase of the outcomes of my material and digital explorations in the form of installation, sculpture and film. My primary motivation can be described as a relational and ethical attempt to find a balance between the erotic and the aggressive. This is experienced in the self as feelings of attraction and repulsion in response to the new and unknown "other". Consequently creative practice is necessarily a complex affair that is experienced as a completely immersive and self-contained psychological space. It is within this space that both physical sensation and raw emotion are able to tangibly and conceptually interact with psychoanalytic theory, and concrete materials video and sound.

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This creative writing work was selected for publication in a bi-lingual anthology, published in China, as suitable to be culturally applicable to both Chinese and Australian social contexts. The poem raises six social/ethical issues and comments on them. It is based on research into Chinese traditional poetry that focuses on an image, and after each image this poem provides an ethical comment. It is based in the ethical hypothesis that moral evaluation of individual and social behaviour can not be achieved without ethical judgement which questions social norms. In particular, the poem questions the validity of fundamentalism – the belief in religious, scientific and moral absolutes. This is a key issue in contemporary research into the effect of religion on politics. It also draws on contemporary psychological theory, especially the concept of narcissism. The sociological basis of the work is in drawing parallels between eastern and western ethical issues, stressing similarity by inference. The imagery on which the poem is based selects objects such a single ‘stone’ that take on symbolic connotations common to both Australian and Chinese readers. This is innovative, since very little creative writing has been dome to address commonalities between Australian and Chinese ethical thinking, especially by adopting Chinese motifs.

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In 1997, business trend analyst Linda Stone proposed the term "continuous partial attention" to characterise the contemporary experience of wanting to be ‘a live node on the network’. She argued that while it can be a positive and functional behaviour, it also has the potential to be disabling, compromising reflective and creative thought. Subsequent studies have explored the ways in which technology has slowly disrupted the idea and experience of a "centred" and "bounded" self. Studies of ‘Gen Y’ show the ease with which young people accommodate this multiplying of the self as they negotiate their partial friendships and networks of interest with family and work. In teaching and learning circles in tertiary education we talk a lot about problems of student ‘disengagement’. In characterising our challenge this way, are we undermining our potential to understand the tendencies of contemporary learners? This paper begins a consideration of how traditional models, frameworks and practices might oppose these partially engaged but continuously connected and interpersonal "dividuals". What questions does this provoke for learning environments towards harnessing yet counterpointing the crisis students might experience; to recognise but also integrate their multiple selves towards what they aim to become through the process of learning?

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The lava park is surrounded by the volcanic mountains of Les Preses, revealed as the edges of a vast caldera and repeated at a human scale with low walls made up of small volcanic boulders. These walls are evidence of how successive communities have gradually worked amongst this lava flow to create arable land, supported by rich soils. The people saw the land prosper and learned how to maximise its productivity. Boulders that had come to the surface during agricultural cultivation were moved with human labour to create "artigas“, the characteristic pilings of volcanic stone. They have been used to raise and lower areas, to create shelter and exposure for their crops and to make caves for storage. Amongst all this, paths weave and cross. The whole place is made up of grey and black rocks with a constant cover of green crops or grass.

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Raman spectroscopy has been used to characterise the antimonate mineral bahianite Al5Sb35+O14(OH)2 , a semi-precious gem stone. The mineral is characterised by an intense Raman band at 818 cm-1 assigned to Sb3O1413- stretching vibrations. Other lower intensity bands at 843 and 856 cm-1 are also assigned to this vibration and this concept suggests the non-equivalence of SbO units in the structure. Low intensity Raman bands at 669 and 682 cm-1 are probably assignable to the OSbO antisymmetric stretching vibrations. Raman bands at 1756, 1808 and 1929 cm-1 may be assigned to δ SbOH deformation modes, whilst Raman bands at 3462 and 3495 cm-1 are assigned to AlOH stretching vibrations. Complexity in the low wave number region is attributed to the composition of the mineral.

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YEAR: 2008 ROLE: Performer FORMAT: Live Art Event at Tiananmen Square Beijing, China (3 hours) and Later on Summit of Mt. Tai Shan, Shandong Province, China (6 hrs + 3 hrs). WITH: Solo WHAT: In the Hall of Reverence on Tiananmen Square, Beijing Mao Zedong's body lies in state surrounded by flowers and draped with a Red Flag of Communist China. His casket with a glass top lies on a black stone from Mt. Tai, reflecting the quotation from Sima Qian (China's Han Dynasty historian) that "One's life can be weightier than Mt. Tai or lighter than a goose feather". This pair of performances were a quiet, personal reflection upon what such a once revolutionary expression might mean in today's very different time and place. The work was conceived during the Olympic Cultural Festival showing of Intimate Transactions (www.intimatetransactions.com) - during the tumultuous times leading up to China's proudly staged August 2008 Olympics. The rise and rise of China had long been generating major geopolitical, ecological and cross-cultural shifts throughout the region and beyond. In this dramatic epicentre of change and at a time of such great national pride, how might we each act in ways that are ecologically 'mighty' and yet simultaneously have an impact lighter than a goosefeather? This is both a question for China in its relations with the autonomous provinces and the environment as it is for all of us in our own 'local' affairs. However ecologically speaking all that is of local concern is of global concern and noone can therefore be exempt from the need to sustain that which we share in common and must all protect for the future. Performance 1: Tiananmen Square, Beijing: Dropping 100 goose feathers. Performance 2: The summit of Mt Tai, Shandong Province. Building a mountain from Goose Feathers. SHOWING HISTORY: 1: Anniversary of Protest Crackdown, Jun 8th 2008. 2: Dawn on Tai Shan's summit, 15th June, 2008 DETAILS: Performance 1: Begin an hour after dawn (5.45am) in Tiananmen Square Bring pre-prepared performance shirt, a bag of goose feathers tipped with red. Begin at the "Gate of Heavenly Peace" under the image of Chairman Mao. Circumnavigate the world's largest open and the most surveilled public space 5 times dropping feathers periodically. Meditate on Forces of Change. Finally enter Chairman Mao's mausoleum with the masses and move quietly past his preserved body. End the performance at the Gate of Heavenly Peace 3 hours later. Performance 2: Walk up Mt. Tai Shan in silence meditating on Forces of Change (6 hours). Stay overnight on the summit. Begin an hour before dawn (3.45am) in silence. Bring performance shirt, a sack of goose feathers and a simple wooden structure. On the sunrise viewing side of the mountain build a miniature, fragile 'mountain' in goose feathers and sticks on the edge of a sheer precipice. Watch the sun rise as the feathers blow away into the valley deep below (3 hours).