884 resultados para Resultant
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Combustion behaviour of ammonium perchlorate-potassium perchlorate pellets is studied using Crawford strand burners. At low concentrations of potassium perchlorate (up to 30 percent potassium perchlorate) the burning rate of ammonium perchlorate-potassium perchlorate condensed mixtures increases with potassium perchlorate content. Above 40 percent potassium perchlorate content, combustion sustenance becomes difficult. Decomposition products of ammonium perchlorate sensitize the melting and subsequent decomposition of potassium perchlorate. The results are explained in terms of the melt layer thickness, flame temperature and the resultant surface temperature, and heat wave penetration into the solid. The study suggests the importance of melt layer on the burning surface in the deflagration behaviour of ammonium perchlorate-potassium perchlorate condensed mixtures
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The eradication of an invasive plant species can provide substantial ecological and economic benefits by eliminating completely the negative effects of the weed and reducing the high cost of continuing control. A 5-yr program toward the eradication of hill raspberry (Rubus niveus Thunb.) in Santiago Island is evaluated using delimitation and extirpation criteria, as well as assessment of the ecological community response to management techniques. Currently, hill raspberry is located in the humid zone of Santiago island. It is distributed over three main infestations, small patches, and many scattered individuals within an area of approximately 1,000 ha. New infestations are constantly being found; every year, new detections add an area of approximately 175 ha. Adult and juvenile individuals are still found, both beyond and within known infestations. Both plant and seed bank density of hill raspberry decreased over time where infestations were controlled. Species composition in the seed bank and existing vegetation were significantly different between areas under intensive control and adjacent uninvaded forest. After 5 yr of intensive management, delimitation of hill raspberry has not been achieved; new populations are found every year, increasing the infested area that requires management. Off-target effects on native species resulting from control efforts seem to be substantial. Although a vast increase in economic investment would allow intensive searching that might enable all individuals to be found and controlled, the resultant disturbance and off-targets effects could outweigh the conservation benefits of eradication.
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A TEM study of the interphase boundary structure of 9R orthorhombic alpha1' martensite formed in beta' Cu---Zn alloys shows that it consists of a single array of dislocations with Burgers vector parallel to left angle bracket110right-pointing angle beta and spaced about 3.5 nm apart. This Burgers vector lies out of the interface plane; hence the interface dislocations are glissile. Unexpectedly, though, the Burgers vectors of these dislocations are not parallel when referenced to the matrix and the martensite lattices. This finding is rationalized on published hard sphere models as a consequence of relaxation of a resultant of the Bain strain and lattice invariant shear displacements within the matrix phase.
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Coal seam gas (CSG) is a growing industry in Queensland and represents a potential major employer and deliverer of financial prosperity for years to come. CSG is a natural gas composed primarily of methane and is found trapped underground in coal beds. During the gas extraction process, significant volumes of associated water are also produced. This associated water could be a valuable resource, however, the associated water comprises of various salt constituents that make it problematic for beneficial use. Consequently, there is a need to implement various water treatment strategies to purify the associated water to comply with Queensland’s strict guidelines and to mitigate environmental risks. The resultant brine is also of importance as ultimately it also has to be dealt with in an economical manner. In some ways it can be considered that the CSG industry does not face a water problem, as this has inherent value to society, but rather has a “salt issue” to solve. This study analyzes the options involved in both the water treatment and salt recovery processes. A brief overview of the constituents present in Queensland CS water is made to illustrate the challenges involved and a range of treatment technologies discussed. Water treatment technologies examined include clarification (ballasted flocculation, dissolved air flotation, electrocoagulation), membrane filtration (ultrafiltration), ion exchange softening and desalination (ion exchange, reverse osmosis desalination and capacitance deionization). In terms of brine management we highlighted reinjection, brine concentration ponds, membrane techniques (membrane distillation, forward osmosis), thermal methods, electrodialysis, electrodialysis reversal, bipolar membrane electrodialysis, wind assisted intensive evaporation, membrane crystallization, eutectic freeze crystallization and vapor compression. As an entirety this investigation is designed to be an important tool in developing CS water treatment management strategies for effective management in Queensland and worldwide.
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Emerging zoonoses threaten global health, yet the processes by which they emerge are complex and poorly understood. Nipah virus (NiV) is an important threat owing to its broad host and geographical range, high case fatality, potential for human-to-human transmission and lack of effective prevention or therapies. Here, we investigate the origin of the first identified outbreak of NiV encephalitis in Malaysia and Singapore. We analyse data on livestock production from the index site (a commercial pig farm in Malaysia) prior to and during the outbreak, on Malaysian agricultural production, and from surveys of NiV's wildlife reservoir (flying foxes). Our analyses suggest that repeated introduction of NiV from wildlife changed infection dynamics in pigs. Initial viral introduction produced an explosive epizootic that drove itself to extinction but primed the population for enzootic persistence upon reintroduction of the virus. The resultant within-farm persistence permitted regional spread and increased the number of human infections. This study refutes an earlier hypothesis that anomalous El Nino Southern Oscillation-related climatic conditions drove emergence and suggests that priming for persistence drove the emergence of a novel zoonotic pathogen. Thus, we provide empirical evidence for a causative mechanism previously proposed as a precursor to widespread infection with H5N1 avian influenza and other emerging pathogens.
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UNCITRAL’s operation as a subsidiary of the UN General Assembly, tasked to unify and harmonise international trade law is a necessary and indispensable element of the UN’s mandate to maintain international peace and security. Strong legal frameworks which are compatible with those of international trading partners often accompany accelerated growth in economic capacity and stability. Over time, access to markets and resultant growth in economic and human development creates a disincentive for instability as incomes and standards of living rise. Human and economic development, facilitated by a modernised and just legal framework that is available to the broadest range of recipients goes hand in hand with the maintenance of domestic and regional peace, particularly in regions such as the ASEAN , one of the fastest growing in the world covering approximately 30% of global population and with a number of strong global economic neighbours including Japan, Korea, China (to the north), Australia (to the south) and Singapore (to the west). In an increasingly interconnected world, the ability of government, enterprise and individuals to participate in the global supply chain offers opportunities for economic growth and development. Over its almost 50 years of operations, UNCITRAL has produced a range of important texts that are designed to underpin world trade. A key implicit assumption underpinning the development of UNCITRAL texts is that the texts, once adopted can and will be applied in adopting states.
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Background:Quantifying genetic diversity and metapopulation structure provides insights into the evolutionary history of a species and helps develop appropriate management strategies. We provide the first assessment of genetic structure in spinner sharks (Carcharhinus brevipinna), a large cosmopolitan carcharhinid, sampled from eastern and northern Australia and South Africa. Methods and Findings:Sequencing of the mitochondrial DNA NADH dehydrogenase subunit 4 gene for 430 individuals revealed 37 haplotypes and moderately high haplotype diversity (h = 0.6770 ±0.025). While two metrics of genetic divergence (ΦST and FST) revealed somewhat different results, subdivision was detected between South Africa and all Australian locations (pairwise ΦST, range 0.02717–0.03508, p values ≤ 0.0013; pairwise FST South Africa vs New South Wales = 0.04056, p = 0.0008). Evidence for fine-scale genetic structuring was also detected along Australia’s east coast (pairwise ΦST = 0.01328, p < 0.015), and between south-eastern and northern locations (pairwise ΦST = 0.00669, p < 0.04).Conclusions: The Indian Ocean represents a robust barrier to contemporary gene flow in C. brevipinna between Australia and South Africa. Gene flow also appears restricted along a continuous continental margin in this species, with data tentatively suggesting the delineation of two management units within Australian waters. Further sampling, however, is required for a more robust evaluation of the latter finding. Evidence indicates that all sampled populations were shaped by a substantial demographic expansion event, with the resultant high genetic diversity being cause for optimism when considering conservation of this commercially-targeted species in the southern Indo-Pacific.
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The rail-sleeper system is idealized as an infinite, periodic beam-mass system. Use is made of the periodicity principle for the semi-infinite halves on either side of the forcing point for evaluation of the wave propagation constants and the corresponding modal vectors. It is shown that the spread of acceleration away from the forcing point depends primarily upon one of the wave propagation constants. However, all the four modal vectors (two for the left-hand side and two for the right-hand side) determine the driving point impedance of the rail-sleeper system, which in combination with the driving point impedance of the wheel (which is adopted from the preceding companion paper) determines the forces generated by combined surface roughness and the resultant accelerations. The compound one-third octave acceleration levels generated by typical roughness spectra are generally of the same order as the observed levels.
Prevalence and incidence of shoulder and neck dysfunction after neck dissection: A systematic review
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Background: Head and neck cancer is a debilitating disease. Not only can the primary tumour cause painful swallowing and speech difficulties, the treatments required to manage it can impact on neck and shoulder musculoskeletal function. In particular, those patients who undergo neck dissection surgery to remove lymph nodes from the neck can acquire accessory nerve injury during the procedure and a resultant loss of shoulder/neck motion, strength and function. Despite changes to surgical techniques that can protect the nerve, patients still report problems post-operatively.
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Many authors have noted that consumer confidence in buying fresh flowers is strongly related to their perceived value in that quality and vase life must be high and consistent over time for consumers to repeat buy. Growers, wholesalers, exporters and retailers seek practical information about recommended handling and treatments at the harvest and postharvest stages, including that relating to flowers native to Australia and South Africa ("wildflowers"). This information is essential for products to be of high quality with an acceptable vase life for the end consumer, especially if exported. Published postharvest manuals generally focus on traditional flower crops and so rarely include many, or any, wildflowers. A manual entitled Postharvest Handling of Australian flowers from Native Plants and Related Species was published in 2002 and addressed this gap, but required updating. This situation presented an opportunity to provide in-depth information to compliment the Australian wildflower quality specifications (see accompanying paper in the same volume), and to assemble the latest knowledge on wildflower quality and postharvest issues. The resultant manual contains extensive information about harvesting, quality issues and recommended postharvest care focussed on wildflowers. Much of the information is documented for the first time, being based on the most up to date research and development (R&D) as well as practical experience of the floral supply chain, researchers and other technical experts. The manual provides practical and detailed information on postharvest treatment of fresh wildflowers for growers, florists, wholesalers and exporters to use on a daily basis. It discusses the many unique features of wildflowers that must be understood and managed in order to maximise their quality and vase life after marketing and export. The manual also includes postharvest advice for 16 flower- and foliage lines for which quality specifications were not produced. This advice is presented according to the same template as the specifications.
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The notions of identity and teacher education have attracted considerable research over the years, revealing a strong correlation between teacher beliefs and practices and the resultant impact on pedagogical practices in the classroom. In an era where the use of digital technologies should be synonymous with teacher pedagogical practices and transforming education, there is a growing need for pre-service teachers to develop an identity that resonates with pedagogical practices that engage and connect with students in a positive and productive way. With many educational institutions also mandating that educators use digital technologies as a tool to support and enhance teaching, pre-service teacher education needs to ensure that students understand and develop a positive identity within this digital world. Current literature acknowledges that many educators adopt digital technologies in the classroom without sometimes fully understanding its scope or impact. It is within this context that this paper reports on a three-year study of first year pre-service education students and their understanding of identity in a digital world. More specifically, the study identifies how students currently use social and digital media in their personal and professional lives to identify themselves online in order to promote a positive image. The study also seeks to identify how these technologies and an understanding of identity can be utilised to promote a positive first year experience.
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Indospicine is a non-proteinogenic amino acid which occurs in Indigofera species with widespread prevalence in grazing pastures across tropical Africa, Asia, Australia, and the Americas. It accumulates in the tissues of grazing livestock after ingestion of Indigofera. It is a competitive inhibitor of arginase and causes both liver degeneration and abortion. Indospicine hepatoxicity occurs universally across animal species but the degree varies considerably between species, with dogs being particularly sensitive. The magnitude of canine sensitivity is such that ingestion of naturally indospicine-contaminated horse and camel meat has caused secondary poisoning of dogs, raising significant industry concern. Indospicine impacts on the health and production of grazing animals per se has been less widely documented. Livestock grazing Indigofera have a chronic and cumulative exposure to this toxin, with such exposure experimentally shown to induce both hepatotoxicity and embryo-lethal effects in cattle and sheep. In extensive pasture systems, where animals are not closely monitored, the resultant toxicosis may well occur after prolonged exposure but either be undetected, or even if detected not be attributable to a particular cause. Indospicine should be considered as a possible cause of animal poor performance, particularly reduced weight gain or reproductive losses, in pastures where Indigofera are prevalent.
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Aim To assess the effectiveness of a decision support intervention using a pragmatic single blind Randomized Controlled Trial. Background Worldwide the proportion of older people (aged 65 years and over) is rising. This population is known to have a higher prevalence of chronic diseases including chronic kidney disease. The resultant effect of the changing health landscape is seen in the increase in older patients (aged ≥65 years) commencing on dialysis. Emerging evidence suggests that for some older patients dialysis may provide minimal benefit. In a majority of renal units non-dialysis management is offered as an alternative to undertaking dialysis. Research regarding decision-making support that is required to assist this population in choosing between dialysis or non-dialysis management is limited. Design. A multisite single blinded pragmatic randomized controlled trial is proposed. Methods Patients will be recruited from four Queensland public hospitals and randomizd into either the control or intervention group. The decision support intervention is multimodal and includes counselling provided by a trained nurse. The comparator is standard decision-making support. The primary outcomes are decisional regret and decisional conflict. Secondary outcomes are improved knowledge and quality of life. Ethics approval obtained November 2014. Conclusion This is one of the first randomized controlled trials assessing a decision support intervention in older people with advance chronic kidney disease. The results may provide guidance for clinicians in future approaches to assist this population in decision-making to ensure reduced decisional regret and decisional conflict.
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A simple, rapid and efficient procedure for the purification of thiamin-binding protein from chicken egg yolk was developed. The method involved removal, by exclusion, of lipoproteins from DEAE-cellulose and subsequent elution of water-soluble proteins held on the ion-exchanger with 1 M-NaCl, followed by treatment of the eluted protein fraction with an aqueous suspension of dextran/charcoal to generate apoprotein from the holoprotein. The resultant protein fraction was subjected to bioaffinity chromatography on thiamin pyrophosphate--AE (aminoethyl)-Sepharose. The protein eluted specifically with 10 microM-thiamin at pH 7.0, was homogeneous by the criteria of polyacrylamide-gel disc electrophoresis, had a mol.wt. of 38 000 +/- 2000 and was not a glycoprotein. The purified thiamin-binding protein specifically interacted with riboflavin-binding protein with no detectable deleterious affect on its (14C)thiamin-binding capacity. The protein bound [14C]thiamin with a molar ratio of 1.0, with dissociation constant (Kd) 0.41 microM. This protein-ligand interaction was inhibited by thiamin analogues and antagonists. The absorption spectrum of the protein in the presence of thiamin exhibited significant hypochromism at the 278 nm band, indicating the involvement of aromatic amino acid residues of the protein, during its binding to the ligand. The protein cross-reacted with the monospecific antiserum to egg-white thiamin-binding protein, showing thereby that thiamin-binding proteins present in chicken egg yolk and white are the products of the same structural gene.
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Foot problems complicating diabetes are a source of major patient suffering and societal costs. Investing in evidence-based, internationally appropriate diabetic foot care guidance is likely among the most cost-effective forms of healthcare expenditure, provided it is goal-focused and properly implemented. The International Working Group on the Diabetic Foot (IWGDF) has been publishing and updating international Practical Guidelines since 1999. The 2015 updates are based on systematic reviews of the literature, and recommendations are formulated using the Grading of Recommendations Assessment Development and Evaluation system. As such, we changed the name from 'Practical Guidelines' to 'Guidance'. In this article we describe the development of the 2015 IWGDF Guidance documents on prevention and management of foot problems in diabetes. This Guidance consists of five documents, prepared by five working groups of international experts. These documents provide guidance related to foot complications in persons with diabetes on: prevention; footwear and offloading; peripheral artery disease; infections; and, wound healing interventions. Based on these five documents, the IWGDF Editorial Board produced a summary guidance for daily practice. The resultant of this process, after reviewed by the Editorial Board and by international IWGDF members of all documents, is an evidence-based global consensus on prevention and management of foot problems in diabetes. Plans are already under way to implement this Guidance. We believe that following the recommendations of the 2015 IWGDF Guidance will almost certainly result in improved management of foot problems in persons with diabetes and a subsequent worldwide reduction in the tragedies caused by these foot problems.