188 resultados para radius fractures
Resumo:
Background: The incidence of mandibular fractures in the Northern Territory of Australia is very high, especially among Indigenous people. Alcohol intoxication is implicated in the majority of facial injuries, and substance use is therefore an important target for secondary prevention. The current study tests the efficacy of a brief therapy, Motivational Care Planning, in improving wellbeing and substance misuse in youth and adults hospitalised with alcohol-related facial trauma. Methods and design: The study is a randomised controlled trial with 6 months of follow-up, to examine the effectiveness of a brief and culturally adapted intervention in improving outcomes for trauma patients with at-risk drinking admitted to the Royal Darwin Hospital maxillofacial surgery unit. Potential participants are identified using AUDIT-C questionnaire. Eligible participants are randomised to either Motivational Care Planning (MCP) or Treatment as Usual (TAU). The outcome measures will include quantity and frequency of alcohol and other substance use by Timeline Followback. The recruitment target is 154 participants, which with 20% dropout, is hoped to provide 124 people receiving treatment and follow-up. Discussion: This project introduces screening and brief interventions for high-risk drinkers admitted to the hospital with facial trauma. It introduces a practical approach to integrating brief interventions in the hospital setting, and has potential to demonstrate significant benefits for at-risk drinkers with facial trauma.
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Background: Understanding the spatial distribution of suicide can inform the planning, implementation and evaluation of suicide prevention activity. This study explored spatial clusters of suicide in Australia, and investigated likely socio-demographic determinants of these clusters. Methods: National suicide and population data at a statistical local area (SLA) level were obtained from the Australian Bureau of Statistics for the period of 1999 to 2003. Standardised mortality ratios (SMR) were calculated at the SLA level, and Geographic Information System (GIS) techniques were applied to investigate the geographical distribution of suicides and detect clusters of high risk in Australia. Results: Male suicide incidence was relatively high in the northeast of Australia, and parts of the east coast, central and southeast inland, compared with the national average. Among the total male population and males aged 15 to 34, Mornington Shire had the whole or a part of primary high risk cluster for suicide, followed by the Bathurst-Melville area, one of the secondary clusters in the north coastal area of the Northern Territory. Other secondary clusters changed with the selection of cluster radius and age group. For males aged 35 to 54 years, only one cluster in the east of the country was identified. There was only one significant female suicide cluster near Melbourne while other SLAs had very few female suicide cases and were not identified as clusters. Male suicide clusters had a higher proportion of Indigenous population and lower median socio-economic index for area (SEIFA) than the national average, but their shapes changed with selection of maximum cluster radii setting. Conclusion: This study found high suicide risk clusters at the SLA level in Australia, which appeared to be associated with lower median socio-economic status and higher proportion of Indigenous population. Future suicide prevention programs should focus on these high risk areas.
Resumo:
Orthopaedics and Trauma Queensland, a Centre for Research and Education in Musculoskeletal Disorders, is an internationally recognised research group that is developing into an international leader in research and education. It provides a stimulus for research, education and clinical application within the international orthopaedic and trauma communities. Orthopaedics and Trauma Queensland develops and promotes the innovative use of engineering and technology, in collaboration with surgeons, to provide new techniques, materials, procedures and medical devices. Its integration with clinical practice and strong links with hospitals ensure that the research will be translated into practical outcomes for patients. The group undertakes clinical practice in orthopaedics and trauma and applies core engineering skills to challenges in medicine. The research is built on a strong foundation of knowledge in biomedical engineering, and incorporates expertise in cell biology, mathematical modelling, human anatomy and physiology and clinical medicine in orthopaedics and trauma. New knowledge is being developed and applied to the full range of orthopaedic diseases and injuries, such as knee and hip replacements, fractures and spinal deformities.
Resumo:
Context: The benefits of high serum levels of 25-hydroxyvitamin D [25(OH)D] are unclear. Trials are needed to establish an appropriate evidence base. Objective: We plan to conduct a large-scale trial of vitamin D supplementation for the reduction of cancer incidence and overall mortality and report here the methods and results of a pilot trial established to inform its design. Design: Pilot D-Health was a randomized trial carried out in a general community setting with 12 months intervention and follow-up. Participants: Participants were 60- to 84-yr-old residents of one of the four eastern Australian states who did not have any vitamin D-related disorders and who were not taking more than 400 IU supplementary vitamin D per day. A total of 644 participants were randomized, and 615 completed the study (two persons withdrew because of nonserious adverse events). Interventions: The interventions were monthly doses of placebo or 30,000 or 60,000 IU vitamin D3. Main Outcomes: The main outcomes were the recruitment rate and changes in serum 25(OH)D. Results: Ten percent of those approached were recruited. At baseline, the mean 25(OH)D was 42 nmol/liter in all three study arms. The mean change in 25(OH)D in the placebo group was 0.12 nmol/liter, compared with changes of 22 and 36 nmol/liter in the 30,000- and 60,000-IU groups, respectively. Conclusions: The D-Health pilot has shown that a large trial is feasible in Australia and that a dose of 2000 IU/d will be needed to ensure that a large proportion of the population reaches the target serum 25(OH)D level. Copyright © 2012 by The Endocrine Society.
Resumo:
Superconducting Bi-2212 tapes and laminates are fabricated by a combination of dip-coating and partial melt processing. The heat treated tapes have critical current densities (Jc) up to 11 kAcm -2. We investigate the degradation of critical current (Ic) during bending experiments for both single tapes and tapes with laminate structure. Although degradation of Ic is observed in both forms, the characteristics of the degradation differ. It is determined that laminated tapes perform better than single tapes when critical current is measured against bending radius, and laminated tapes tolerate a higher strain for a given reduction in critical current. It is found that increasing the number of Bi-2212 layers increases the total Ic of the laminated tape, but degradation of critical current is more pronounced during bending because of the increased total thickness of the laminate structure. It is also found that addition of silver to the Bi-2212 layers reduces critical current degradation during bending for both tapes and laminates.
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Intercalated Archean komatiites and dacites sit above a thick footwall dacite unit in the host rock succession at the Black Swan Nickel Mine, north of Kalgoorlie in the Yilgarn Craton, Western Australia. Both lithofacies occur in units that vary in scale from laterally extensive at the scale of the mine lease to localized, thin, irregular bodies, from > 100 m thick to only centimetres thick. Some dacites are only slightly altered and deformed, and are interpreted to post-date major deformation and alteration (late porphyries). However, the majority of the dacites display evidence of deformation, especially at contacts, and metamorphism, varying from silicification and chlorite alteration at contacts to pervasive low grade regional metamorphic alteration represented by common assemblages of chlorite, sericite and albite. Texturally, the dacites vary from entirely massive and coherent to partially brecciated to totally brecciated. Strangely, some dacites are coherent at the margins and brecciated internally. Breccia textures vary from cryptically defined, to blocky, closely packed, in situ jig-saw fit textures with secondary minerals in fractures between clasts, to more apparent matrix rich textures with round clast forms, giving apparent conglomerate textures. Some clast zones have multi-coloured clasts, giving the impression of varied provenance. Strangely however, all these textural variants have gradational relationships with each other, and no bedding or depositional structures are present. This indicates that all textures have an in situ origin. The komatiites are generally altered and pervasively carbonate veined. Preservation of original textures is patchy and local, but includes coarse adcumulate, mesocumulate, orthocumulate, crescumulate-harrisite and occasionally spinifex textures. Where original contacts between komatiites and dacites are preserved intact (i.e. not sheared or overprinted by alteration), the komatiites have chilled margins, whereas the dacites do not. The margins of the dacites are commonly silicified, and inclusions of dacite occur in komatiite, even at the top contacts of komatiite units, but komatiite clasts do not occur in the dacites. The komatiites therefore were emplaced as sills into the dacites, and the intercalated relationships are interpreted as intrusive. The brecciation and alteration in the dacites are interpreted as being largely due to hydraulic fracturing and alteration induced by contact metamorphic effects and hydrothermal alteration deriving from the intrusion of komatiites into the felsic pile. The absence of autobreccia and hyaloclastite textures in the dacites suggest that they were emplaced as an earlier intrusive (sill?) complex at a high level in the crust.
Resumo:
The influence of different electrolyte cations ((Li+, Na+, Mg2+, tetrabutyl ammonium (TBA+)) on the TiO2 conduction band energy (Ec) the effective electron lifetime (τn), and the effective electron diffusion coefficient (Dn) in dye-sensitized solar cells (DSCs) was studied quantitatively. The separation between Ec and the redox Fermi level, EF,redox, was found to decrease as the charge/radius ratio of the cations increased. Ec in the Mg2+ electrolyte was found to be 170 meV lower than that in the Na+ electrolyte and 400 meV lower than that in the TBA+ electrolyte. Comparison of Dn and τn in the different electrolytes was carried out by using the trapped electron concentration as a measure of the energy difference between Ec and the quasi-Fermi level, nEF, under different illumination levels. Plots of Dn as a function of the trapped electron density, nt, were found to be relatively insensitive to the electrolyte cation, indicating that the density and energetic distribution of electron traps in TiO2 are similar in all of the electrolytes studied. By contrast, plots of τn versus nt for the different cations showed that the rate of electron back reaction is more than an order of magnitude faster in the TBA+ electrolyte compared with the Na+ and Li+ electrolytes. The electron diffusion lengths in the different electrolytes followed the sequence of Na+ > Li+ > Mg2+ > TBA+. The trends observed in the AM 1.5 current–voltage characteristics of the DSCs are rationalized on the basis of the conduction band shifts and changes in electron lifetime.
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Small-angle and ultra-small-angle neutron scattering (SANS and USANS), low-pressure adsorption (N2 and CO2), and high-pressure mercury intrusion measurements were performed on a suite of North American shale reservoir samples providing the first ever comparison of all these techniques for characterizing the complex pore structure of shales. The techniques were used to gain insight into the nature of the pore structure including pore geometry, pore size distribution and accessible versus inaccessible porosity. Reservoir samples for analysis were taken from currently-active shale gas plays including the Barnett, Marcellus, Haynesville, Eagle Ford, Woodford, Muskwa, and Duvernay shales. Low-pressure adsorption revealed strong differences in BET surface area and pore volumes for the sample suite, consistent with variability in composition of the samples. The combination of CO2 and N2 adsorption data allowed pore size distributions to be created for micro–meso–macroporosity up to a limit of �1000 Å. Pore size distributions are either uni- or multi-modal. The adsorption-derived pore size distributions for some samples are inconsistent with mercury intrusion data, likely owing to a combination of grain compression during high-pressure intrusion, and the fact that mercury intrusion yields information about pore throat rather than pore body distributions. SANS/USANS scattering data indicate a fractal geometry (power-law scattering) for a wide range of pore sizes and provide evidence that nanometer-scale spatial ordering occurs in lower mesopore–micropore range for some samples, which may be associated with inter-layer spacing in clay minerals. SANS/USANS pore radius distributions were converted to pore volume distributions for direct comparison with adsorption data. For the overlap region between the two methods, the agreement is quite good. Accessible porosity in the pore size (radius) range 5 nm–10 lm was determined for a Barnett shale sample using the contrast matching method with pressurized deuterated methane fluid. The results demonstrate that accessible porosity is pore-size dependent.
Resumo:
Purpose. The purpose of this article was to present methods capable of estimating the size and shape of the human eye lens without resorting to phakometry or magnetic resonance imaging (MRI). Methods. Previously published biometry and phakometry data of 66 emmetropic eyes of 66 subjects (age range [18, 63] years, spherical equivalent range [−0.75, +0.75] D) were used to define multiple linear regressions for the radii of curvature and thickness of the lens, from which the lens refractive index could be derived. MRI biometry was also available for a subset of 30 subjects, from which regressions could be determined for the vertex radii of curvature, conic constants, equatorial diameter, volume, and surface area. All regressions were compared with the phakometry and MRI data; the radii of curvature regressions were also compared with a method proposed by Bennett and Royston et al. Results. The regressions were in good agreement with the original measurements. This was especially the case for the regressions of lens thickness, volume, and surface area, which each had an R2 > 0.6. The regression for the posterior radius of curvature had an R2 < 0.2, making this regression unreliable. For all other regressions we found 0.25 < R2 < 0.6. The Bennett-Royston method also produced a good estimation of the radii of curvature, provided its parameters were adjusted appropriately. Conclusions. The regressions presented in this article offer a valuable alternative in case no measured lens biometry values are available; however care must be taken for possible outliers.
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Bird communities were studied in two subregional areas of Cravens Peak, the Toko Plains and the Simpson-Strzelecki Dunefields, using the point counts method. A total of 42 2ha 20 minute surveys, 46 five-hundred metre radius area surveys and 170 5km drive through area surveys were conducted and observations made. Bird species were identified, counted and recorded. The data were compared in the two subregions and, as a whole, considering species groups according to land system on which the ecosystem occurs, the specific ecosystem and according to their general feeding habits (insectivore, omnivore, frugivore, granivore, nectarivore and carnivore). Species richness and species relative abundance were compared using Simpson’s Diversity Index and the data revealed that species are distributed largely on the basis of habitat. In general, areas with a greater number of vegetation strata recorded greater species diversity. Overall, the Tall Open Acacia georginae Shrubland on alluvial floodplains has a greater diversity of birds in a 2ha area (0.87, Simpson’s Index of Diversity 1-D) compared to the other survey sites.
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Bird coastal communities were studied along Bribie Island and Moreton Island, two islands within Moreton Bay, Brisbane, Queensland, Australia, using the point counts method. A total of 128 five-hundred metre radius area surveys and 81 beach drive surveys were conducted and observations made over four seasons. Bird species were identified, counted and recorded. The data was compared between the two islands and, between sites on each island as oil-spill affected sites to non-oil spill affected sites. Species such as waders, shorebirds, terns/gulls and raptors were identified as species at most risk from an oil spill and the data was selected to look mainly at these species. The data indicated that sites affected by the oil spill contained 50% less oil-affected species than sites not affected by the oil spill. Bribie Island held on average 5 species per site in the oil affected sites compared to 12 species in non-oil affected sites. This same trend was observed on Moreton Island which held 6 species compared to 14 species. Bird data will continue to be counted over several years to determine whether the observed data is a true reflection of the affects of an oil spill on the habitat of shorebirds.
Resumo:
Osteoporosis imposes a tremendous burden on Australia : 1.2 million Australians have osteoporosis and 6.3 million have Osteopenia. In the 2007-08 financial year, 82000 Australians suffered fragility fractures, of Which >17000 were hip fractures. In the 2000-01 financial year, direct costs were estimated at $1.9 billion per year and an additional $5.6 billion on indirect costs. Osteoporosis was designated a National Health Priority Area in 2002; however, implementation of national plans has not yet matched the rhetoric in terms of urgency. Building healthy bones throughout life, the Osteoporosis Australia strategy to prevent osteoporosis throughout the life cycle, presents an evidence-informed set of recommendations for consumers, health care professionals and policymakers. The strategy was adopted by consensus at the Osteoporosis Australia Summit in Sydney, 20 October 2011. Primary objectives throughout the life cycle are: to maximise peak bone mass during childhood and adolescence to prevent premature bone loss and improve or maintain muscle mass, strength and functional capacity in healthy adults to prevent and treat osteoporosis in order to minimise the risk of suffering fragility fractures, and reduce falls risk, in older people. The recommendations focus on three affordable and important interventions to ensure people have adequate calcium intake, vitamin D levels and appropriate, physical activity throughout their lives. Recommendations relevant to all stages of life include: daily dietary calcium intakes should be consistent with Australian and New Zealand guidelines serum levels of vitamin D in the general population should be above 50 nmol/L in winter or early spring for optimal bone health regular weight-bearing physical activity, Muscle strengthening exercises and challenging balance/ mobility activities should be conducted in a safe environment.
A new model to study healing of a complex femur fracture with concurrent soft tissue injury in sheep
Resumo:
High energy bone fractures resulting from impact trauma are often accompanied by subcutaneous soft tissue injuries, even if the skin remains intact. There is evidence that such closed soft tissue injuries affect the healing of bone fractures, and vice versa. Despite this knowledge, most impact trauma studies in animals have focussed on bone fractures or soft tissue trauma in isolation. However, given the simultaneous impact on both tissues a better understanding of the interaction between these two injuries is necessary to optimise clinical treatment. The aim of this study was therefore to develop a new experimental model and characterise, for the first time, the healing of a complex fracture with concurrent closed soft tissue trauma in sheep. A pendulum impact device was designed to deliver a defined and standardised impact to the distal thigh of sheep, causing a reproducible contusion injury to the subcutaneous soft tissues. In a subsequent procedure, a reproducible femoral butterfly fracture (AO C3-type) was created at the sheep’s femur, which was initially stabilised for 5 days by an external fixator construct to allow for soft tissue swelling to recede, and ultimately in a bridging construct using locking plates. The combined injuries were applied to twelve sheep and the healing observed for four or eight weeks (six animals per group) until sacrifice. The pendulum impact led to a moderate to severe circumferential soft tissue injury with significant bruising, haematomas and partial muscle disruptions. Posttraumatic measurements showed elevated intra-compartmental pressure and circulatory tissue breakdown markers, with recovery to normal, pre-injury values within four days. Clinically, no neurovascular deficiencies were observed. Bi-weekly radiological analysis of the healing fractures showed progressive callus healing over time, with the average number of callus bridges increasing from 0.4 at two weeks to 4.2 at eight weeks. Biomechanical testing after sacrifice showed increasing torsional stiffness between four and eight weeks healing time from 10% to 100%, and increasing ultimate torsional strength from 10% to 64% (relative to the contralateral control limb). Our results demonstrate the robust healing of a complex femur fracture in the presence of a severe soft tissue contusion injury in sheep and demonstrate the establishment of a clinically relevant experimental model, for research aimed at improving the treatment of bone fractures accompanied by closed soft tissue injuries.
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A numerical study is presented to examine the fingering instability of a gravity-driven thin liquid film flowing down the outer wall of a vertical cylinder. The lubrication approximation is employed to derive an evolution equation for the height of the film, which is dependent on a single parameter, the dimensionless cylinder radius. This equation is identified as a special case of that which describes thin film flow down an inclined plane. Fully three-dimensional simulations of the film depict a fingering pattern at the advancing contact line. We find the number of fingers observed in our simulations to be in excellent agreement with experimental observations and a linear stability analysis reported recently by Smolka & SeGall (Phys Fluids 23, 092103 (2011)). As the radius of the cylinder decreases, the modes of perturbation have an increased growth rate, thus increasing cylinder curvature partially acts to encourage the contact line instability. In direct competition with this behaviour, a decrease in cylinder radius means that fewer fingers are able to form around the circumference of the cylinder. Indeed, for a sufficiently small radius, a transition is observed, at which point the contact line is stable to transverse perturbations of all wavenumbers. In this regime, free surface instabilities lead to the development of wave patterns in the axial direction, and the flow features become perfectly analogous to the two-dimensional flow of a thin film down an inverted plane as studied by Lin & Kondic (Phys Fluids 22, 052105 (2010)). Finally, we simulate the flow of a single drop down the outside of the cylinder. Our results show that for drops with low volume, the cylinder curvature has the effect of increasing drop speed and hence promoting the phenomenon of pearling. On the other hand, drops with much larger volume evolve to form single long rivulets with a similar shape to a finger formed in the aforementioned simulations.