967 resultados para Standard fire tests


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Worldwide public concern over climate change and the need to limit greenhouse gas (hereafter, GHG) emissions has increasingly motivated public officials to consider more stringent environmental regulation and standards. The authors argue that the development of a new international assurance standard on GHG disclosures is an appropriate response by the auditing and assurance profession to meet these challenges. At its December 2007 meeting, the International Auditing and Assurance Standards Board (hereafter, IAASB) approved a project to consider the development of such a standard aimed at promoting trust and confidence in disclosures of GHG emissions, including disclosures required under emissions trading schemes. The authors assess the types of disclosures that can be assured, and outline the issues involved in developing an international assurance standard on GHG emissions disclosures. The discussion synthesizes the insights gained from four international roundtables on the proposed IAASB assurance standard held in Asia-Pacific, North America, and Europe during 2008, and an IAASB meeting addressing this topic in December 2008.

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We describe the development and parameterization of a grid-based model of African savanna vegetation processes. The model was developed with the objective of exploring elephant effects on the diversity of savanna species and structure, and in this formulation concentrates on the relative cover of grass and woody plants, the vertical structure of the woody plant community, and the distribution of these over space. Grid cells are linked by seed dispersal and fire, and environmental variability is included in the form of stochastic rainfall and fire events. The model was parameterized from an extensive review of the African savanna literature; when available, parameter values varied widely. The most plausible set of parameters produced long-term coexistence between woody plants and grass, with the tree-grass balance being more sensitive to changes in parameters influencing demographic processes and drought incidence and response, while less sensitive to fire regime. There was considerable diversity in the woody structure of savanna systems within the range of uncertainty in tree growth rate parameters. Thus, given the paucity of height growth data regarding woody plant species in southern African savannas, managers of natural areas should be cognizant of different tree species growth and damage response attributes when considering whether to act on perceived elephant threats to vegetation. © 2007 Springer Science+Business Media B.V.

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There is a concern that high densities of elephants in southern Africa could lead to the overall reduction of other forms of biodiversity. We present a grid-based model of elephant-savanna dynamics, which differs from previous elephant-vegetation models by accounting for woody plant demographics, tree-grass interactions, stochastic environmental variables (fire and rainfall), and spatial contagion of fire and tree recruitment. The model projects changes in height structure and spatial pattern of trees over periods of centuries. The vegetation component of the model produces long-term tree-grass coexistence, and the emergent fire frequencies match those reported for southern African savannas. Including elephants in the savanna model had the expected effect of reducing woody plant cover, mainly via increased adult tree mortality, although at an elephant density of 1.0 elephant/km2, woody plants still persisted for over a century. We tested three different scenarios in addition to our default assumptions. (1) Reducing mortality of adult trees after elephant use, mimicking a more browsing-tolerant tree species, mitigated the detrimental effect of elephants on the woody population. (2) Coupling germination success (increased seedling recruitment) to elephant browsing further increased tree persistence, and (3) a faster growing woody component allowed some woody plant persistence for at least a century at a density of 3 elephants/km2. Quantitative models of the kind presented here provide a valuable tool for exploring the consequences of management decisions involving the manipulation of elephant population densities. © 2005 by the Ecological Society of America.

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Background: Malaria rapid diagnostic tests (RDTs) are appropriate for case management, but persistent antigenaemia is a concern for HRP2-detecting RDTs in endemic areas. It has been suggested that pan-pLDH test bands on combination RDTs could be used to distinguish persistent antigenaemia from active Plasmodium falciparum infection, however this assumes all active infections produce positive results on both bands of RDTs, an assertion that has not been demonstrated. Methods: In this study, data generated during the WHO-FIND product testing programme for malaria RDTs was reviewed to investigate the reactivity of individual test bands against P. falciparum in 18 combination RDTs. Each product was tested against multiple wild-type P. falciparum only samples. Antigen levels were measured by quantitative ELISA for HRP2, pLDH and aldolase. Results: When tested against P. falciparum samples at 200 parasites/μL, 92% of RDTs were positive; 57% of these on both the P. falciparum and pan bands, while 43% were positive on the P. falciparum band only. There was a relationship between antigen concentration and band positivity; ≥4 ng/mL of HRP2 produced positive results in more than 95% of P. falciparum bands, while ≥45 ng/mL of pLDH was required for at least 90% of pan bands to be positive. Conclusions: In active P. falciparum infections it is common for combination RDTs to return a positive HRP2 band combined with a negative pan-pLDH band, and when both bands are positive, often the pan band is faint. Thus active infections could be missed if the presence of a HRP2 band in the absence of a pan band is interpreted as being caused solely by persistent antigenaemia.

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This video was prepared as a teaching resource for CARRS-Q's Under the Limit Drink Driving Rehabilitation Program.

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Background The requirement for dual screening of titles and abstracts to select papers to examine in full text can create a huge workload, not least when the topic is complex and a broad search strategy is required, resulting in a large number of results. An automated system to reduce this burden, while still assuring high accuracy, has the potential to provide huge efficiency savings within the review process. Objectives To undertake a direct comparison of manual screening with a semi‐automated process (priority screening) using a machine classifier. The research is being carried out as part of the current update of a population‐level public health review. Methods Authors have hand selected studies for the review update, in duplicate, using the standard Cochrane Handbook methodology. A retrospective analysis, simulating a quasi‐‘active learning’ process (whereby a classifier is repeatedly trained based on ‘manually’ labelled data) will be completed, using different starting parameters. Tests will be carried out to see how far different training sets, and the size of the training set, affect the classification performance; i.e. what percentage of papers would need to be manually screened to locate 100% of those papers included as a result of the traditional manual method. Results From a search retrieval set of 9555 papers, authors excluded 9494 papers at title/abstract and 52 at full text, leaving 9 papers for inclusion in the review update. The ability of the machine classifier to reduce the percentage of papers that need to be manually screened to identify all the included studies, under different training conditions, will be reported. Conclusions The findings of this study will be presented along with an estimate of any efficiency gains for the author team if the screening process can be semi‐automated using text mining methodology, along with a discussion of the implications for text mining in screening papers within complex health reviews.

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This paper reports the details of an experimental study of cold-formed steel hollow section columns at ambient and elevated temperatures. In this study the global buckling behaviour of cold-formed Square Hollow Section (SHS) slender columns under axial compression was investigated at various uniform elevated temperatures up to 700℃. The results of these column tests are reported in this paper, which include the buckling/failure modes at elevated temperatures, and ultimate load versus temperature curves. Finite element models of tested columns were also developed and their behaviour and ultimate capacities at ambient and elevated temperatures were studied. Fire design rules given in European and American standards including the Direct Strength Method (DSM) based design rules were used to predict the ultimate capacities of tested columns at elevated temperatures. Elevated temperature mechanical properties and stress-strain models given in European steel design standards and past researches were used with design rules and finite element models to investigate their effects on SHS column capacities. Comparisons of column capacities from tests and finite element analyses with those predicted by current design rules were used to determine the accuracy of currently available column design rules in predicting the capacities of SHS columns at elevated temperatures and the need to use appropriate elevated temperature material stress-strain models. This paper presents the important findings derived from the comparisons of these column capacities.

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Cold-formed steel members have many advantages over hot-rolled steel members. However, they are susceptible to various buckling modes at stresses below the yield stress of the member because of their relatively high width-to-thickness ratio. Web crippling is a form of localized failure mode that can occur when the members are subjected to transverse high concentrated loadings and/or reactions. The four common loading conditions are the end-one-flange (EOF), interior-one-flange (IOF), end-two-flange (ETF) and interior-two-flange (ITF) loadings. Recently a test method has been proposed by AISI to obtain the web crippling capacities under these four loading conditions. Using this test method 42 tests were conducted in this research to investigate the web crippling behaviour and strengths of unlipped channels with stocky webs under ETF and ITF cases. DuraGal sections having a nominal yield stress of 450 MPa were tested with different web slenderness and bearing lengths. The flanges of these channel sections were not fastened to the supports. In this research the suitability of the currently available design rules for unlipped channels subject to web crippling was investigated, and suitable modifications were proposed where necessary. In addition to this, a new design rule was proposed based on the direct strength method to predict the web crippling capacities of tested beams. This paper presents the details of this experimental study and the results.

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Cold-formed steel members have been widely used in residential and commercial buildings as primary load bearing structural elements. They are often made of thin steel sheets and hence they are more susceptible to local buckling. The buckling behaviour of cold-formed steel compression members under fire conditions is not fully investigated yet and hence there is a lack of knowledge on the fire performance of cold-formed steel compression members. Current cold-formed steel design standards do not provide adequate design guidelines for the fire design of cold-formed steel compression members. Therefore a research project based on extensive experimental and numerical studies was undertaken to investigate the local buckling behaviour of light gauge cold-formed steel compression members under simulated fire conditions. First a series of 91 local buckling tests was conducted at ambient and uniform elevated temperatures up to 700oC on cold-formed lipped and unlipped channels. Suitable finite element models were then developed to simulate the behaviour of tested columns and were validated using test results. All the ultimate load capacity results for local buckling were compared with the predictions from the available design rules based on AS/NZS 4600, BS 5950 Part 5, Eurocode 3 Parts 1.2 and 1.3 and the direct strength method (DSM), based on which suitable recommendations have been made for the fire design of cold-formed steel compression members subject to local buckling at uniform elevated temperatures.

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Background Ugni molinae Turcz. is one of the most studied species of South American Myrtaceae due to its edible fruits and foliar medicinal compounds. However, there is no anatomical study of the leaves or secretory cavities. This paper seeks to describe the leaf micromorphology and anatomy of the species using standard protocols for light and scanning electron microscopy. Secretory cavities were anatomically characterized in young and mature leaves. Histochemical staining of the cavities was performed. Results The leaves of U. molinae are hypostomatic, have a wavy surface and possess scattered hairs. Leaf anatomical features include dorsiventral mesophyll, two to three layers of palisade parenchyma with abundant chloroplasts, calcium oxalate crystals and internal phloem in vascular bundles. Schizogenous secretory cavities are present on the abaxial surface and are mainly located on the margins of the leaves. Histochemical tests of these cavities suggest the presence of lipophilic substances. Conclusions This is the first study of secretory cavities in Chilean Myrtaceae. In general, micromorphological and anatomical characters are similar to other species of the family. The present findings could provide valuable anatomical information for future research in South American Myrtaceae.

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Objective People diagnosed with pancreatic cancer have the worst survival prognosis of any cancer. No previous research has documented the supportive care needs of this population. Our objective was to describe people’s needs and use of support services and to examine whether these differed according to whether or not patients had undergone surgical resection. Methods Queensland pancreatic or ampullary cancer patients (n=136, 54% of those eligible) completed a survey which assessed 34 needs across 5 domains (SCNS-SF34) and use of health services. Differences by resection were compared with Chi-squared tests. Results Overall, 96% of participants reported having some needs. More than half reported moderate-to-high unmet physical (54%) or psychological (52%) needs whereas, health system/information (32%), patient care (21%) and sexuality needs (16%) were described less frequently. The three most frequently reported moderate-to-high needs included ‘not being able to do things they used to do’ (41%), ‘concerns about the worries of those close’ (37%), and ‘uncertainty about the future’ (30%). Patients with non-resectable disease reported greater individual information needs but their needs were otherwise similar to patients with resectable disease. Self-reported use of support was low; only 35% accessed information, 28%, 18% and 15% consulted a dietician, complementary medicine practitioner or mental health practitioner, respectively. Palliative care access was greater (59% vs 27%) among those with non-resectable disease. Conclusion Very high levels of needs were reported by people with pancreatic or ampullary cancer. Future work needs to elucidate why uptake of appropriate supportive care is low and which services are required.

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Thin profiled steel roof sheeting and battens are increasingly used in the construction of roofing systems of residential, commercial, industrial and farm buildings in Australia. The critical load combination of external wind suction and internal wind pressures that occur during high wind events such as thunderstorms and tropical cylcones often dislocate the roofing systems partially or even completely due to premature roof connection failures. Past wind damage investigations have shown that roof sheeting failures occured at their screw connections to battens. In most of these cases, the screw fastener head pulled through the thin roof sheeting whilst the screw fasteners also pulled out from the battens. Research studis undertaken on the roof sheeting to batten connection failures have improved this situation. However, the batten to rafter or truss connections have not been investigated adequately. Failure of these connections can cause the failure of the entire roof structure as observed during the recent high wind events. Therefore a detailed experimental study consisting of both small scale and full scale tests has been undertaken to investigate the steel roof batten pull-through failures in relation to many critical parameters such as steel batten geometry, thickness and grade, screw fastener head sizes and screw tightening. This paper presents the details of this experimental study and the pull-through failure load results obtained from them. Finally it discusses the development of suitable design rules that can be used to determine the pull-through connection capacities of thin steel roof battens under wind uplift loads.

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Today, an Australian parliamentary committee grilled the IT titans - Apple, Adobe, and Microsoft - on price discrimination against Australian consumers. The IT companies were evasive under questioning.

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We usually find low levels of fitness condition affect other aspects of living for people with ID like dependency in carrying out activivities of daily living. Therefore we find high levels of dependency in activities of daily living due to poor fitness condition. The aim of the study is to explore the criterion validity of the Barthel index with a physical fitness test. An observational cross-sectional study was conducted. Data from the Barthel index and a physical fitness test were measured in 122 adults with intellectual disability. The data were analysed to find out the relationship between four categories of the physical fitness test and the Barthel index. It needs to be stressed that the correlations between the Barthel index and leg, abdominal and arm strength can confirm that these physical test are predictive of the Barthel index. The correlations between the balance variables as functional reach and single-leg stance with eyes open shown relationships with Barthel Index. We found important correlations between the physical fitness test and the Barthel index, so we can affirm that some physical fitness features are predictor variables of the Barthel index.