52 resultados para 517 - Anàlisi


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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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Agricultural soils emit about 50% of the global flux of N2O attributable to human influence, mostly in response to nitrogen fertilizer use. Recent evidence that the relationship between N2O fluxes and N-fertilizer additions to cereal maize are non-linear provides an opportunity to estimate regional N2O fluxes based on estimates of N application rates rather than as a simple percentage of N inputs as used by the Intergovernmental Panel on Climate Change (IPCC). We combined a simple empirical model of N2O production with the SOCRATES soil carbon dynamics model to estimate N2O and other sources of Global Warming Potential (GWP) from cereal maize across 19,000 cropland polygons in the North Central Region (NCR) of the US over the period 1964–2005. Results indicate that the loading of greenhouse gases to the atmosphere from cereal maize production in the NCR was 1.7 Gt CO2e, with an average 268 t CO2e produced per tonne of grain. From 1970 until 2005, GHG emissions per unit product declined on average by 2.8 t CO2e ha−1 annum−1, coinciding with a stabilisation in N application rate and consistent increases in grain yield from the mid-1970’s. Nitrous oxide production from N fertilizer inputs represented 59% of these emissions, soil C decline (0–30 cm) represented 11% of total emissions, with the remaining 30% (517 Mt) from the combustion of fuel associated with farm operations. Of the 126 Mt of N fertilizer applied to cereal maize from 1964 to 2005, we estimate that 2.2 Mt N was emitted as N2O when using a non-linear response model, equivalent to 1.75% of the applied N.

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The Raman spectrum of tyrolite, CaCu5(AsO4)2(CO3)(OH) 4.6H2O, from Brixlegg, Tyrol, Austria, is reported. Comparison with copper hydroxy-arsenate and basic carbonates was used to achieve assignments of the observed bands. The AsO43- group is characterized by two υ4 modes around 433 and 480 cm-1 plus a broad band around 840 cm-1 as the υ overlapping with the υ. The υ3 mode is observed as a single band around 355 cm -1. The CO32- υ1 mode is observed around 1035 and 1088 cm-1, although this assignment is difficult because of the in-plane OH bending vibrations at similar frequencies. Two υ4 modes are assigned to the 717 and 755 cm-1 bands. The υ3 mode is present as three bands at 1431, 1463, and 1498 cm-1. A large split caused by bridging carbonates may explain the band at 1370 cm -1. The H2O bending region shows two bands at 1635 and 1667 cm-1 together with stretching modes around 3204 and 3303 cm-1, the first associated with adsorbed H2O, while the second indicates more strongly bonded H2O. Three bands around 3534, 3438, and 3379 cm -1 are assigned to OH stretching modes of the OH groups in the crystal structure. The 202, 262, 301, 524, and 534 cm-1 bands are assigned to Cu-OH bending and stretching modes, whereas the bands around 179, 202, and 217 cm-1 are ascribed to O-(Ca, Cu)-O(H) with the O(H) at much greater distance from the cation. The bands around 503, 570, and 598 cm-1 are ascribed to the Cu-O stretching modes.

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The objective of this research was to develop a question prompt list aimed at increasing question asking and reducing the unmet information needs of adults with primary brain tumours, and to pilot the question prompt list to determine its suitability for the intended population. Thematic analysis of existing resources was used to create a draft which was refined via interviews with 12 brain tumour patients and six relatives, readability testing and review by health professionals. A non-randomised before–after pilot study with 20 brain tumour patients was used to assess the acceptability and usefulness of the question prompt list, compared with a ‘standard brochure’, and the feasibility of evaluation strategies. The question prompt list developed covered seven main topics (diagnosis, prognosis, symptoms and changes, treatment, support, after treatment finishes and the health professional team). Pilot study participants provided with the question prompt list agreed that it was helpful (7/7), contained questions that were useful to them (7/7) and prompted them to ask their medical oncologist questions (5/7). The question prompt list is acceptable to patients and contains questions relevant to them. Research is now needed to assess its effectiveness in increasing question asking and reducing unmet information needs.

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This paper utilizes the Survey of Work History (1981) data to examine the importance of non-random sampling in the context of a model of interfirm labour mobility. The paper adopts Heckman's two-step procedure in order to estimate a three-equation model incorporating an individual's mobility status as endogenously determined. The main conclusion is that in estimating wage equations it is important to consider the role of job mobility and to correct for the effects of sample-selection bias. The results generally accord with those reported by Osberg et al. (1986) in the only previous Canadian study of job mobility in a sample-selection context.

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BACKGROUND: Effective management of chronic diseases such as prostate cancer is important. Research suggests a tendency to use self-care treatment options such as over-the-counter (OTC) complementary medications among prostate cancer patients. The current trend in patient-driven recording of health data in an online Personal Health Record (PHR) presents an opportunity to develop new data-driven approaches for improving prostate cancer patient care. However, the ability of current online solutions to share patients' data for better decision support is limited. An informatics approach may improve online sharing of self-care interventions among these patients. It can also provide better evidence to support decisions made during their self-managed care. AIMS: To identify requirements for an online system and describe a new case-based reasoning (CBR) method for improving self-care of advanced prostate cancer patients in an online PHR environment. METHOD: A non-identifying online survey was conducted to understand self-care patterns among prostate cancer patients and to identify requirements for an online information system. The pilot study was carried out between August 2010 and December 2010. A case-base of 52 patients was developed. RESULTS: The data analysis showed self-care patterns among the prostate cancer patients. Selenium (55%) was the common complementary supplement used by the patients. Paracetamol (about 45%) was the commonly used OTC by the patients. CONCLUSION: The results of this study specified requirements for an online case-based reasoning information system. The outcomes of this study are being incorporated in design of the proposed Artificial Intelligence (Al) driven patient journey browser system. A basic version of the proposed system is currently being considered for implementation.

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This paper reports the findings from a series of scoping interviews designed to evaluate, ground and refine the initial understandings, assumptions and concepts of a research team in a larger project about the role of social and tangible technologies in maintaining good habits into old age. Participants' understandings of some basic terms used in the research are presented along with a discussion of their current use of new and established information and communications technologies and the existing barriers to ongoing uptake of emerging technologies. The findings suggest that we question common assumptions about both ageing and technology usage by ageing people, demonstrating the contribution such early scoping interviews can make within design research projects.

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Non-periodic structural variation has been found in the high Tc cuprates, YBa2Cu3O7-x and Hg0.67Pb0.33Ba2Ca2Cu 3O8+δ, by image analysis of high resolution transmission electron microscope (HRTEM) images. We use two methods for analysis of the HRTEM images. The first method is a means for measuring the bending of lattice fringes at twin planes. The second method is a low-pass filter technique which enhances information contained by diffuse-scattered electrons and reveals what appears to be an interference effect between domains of differing lattice parameter in the top and bottom of the thin foil. We believe that these methods of image analysis could be usefully applied to the many thousands of HRTEM images that have been collected by other workers in the high temperature superconductor field. This work provides direct structural evidence for phase separation in high Tc cuprates, and gives support to recent stripes models that have been proposed to explain various angle resolved photoelectron spectroscopy and nuclear magnetic resonance data. We believe that the structural variation is a response to an opening of an electronic solubility gap where holes are not uniformly distributed in the material but are confined to metallic stripes. Optimum doping may occur as a consequence of the diffuse boundaries between stripes which arise from spinodal decomposition. Theoretical ideas about the high Tc cuprates which treat the cuprates as homogeneous may need to be modified in order to take account of this type of structural variation.

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One of the defences within Part 3-5 of the Australian Consumer Law is the state of the art, or development risk defence. This defence, although significant, has often been neglected in Australian jurisprudential analysis and has triggered at most generic academic analysis. However, with the rise of pharmaceutical and medical device litigation in Australia, it could become a vital weapon for Australian manufacturers against product liability claims. This paper will firstly review the two ways this defence could operate. It will also discuss the three types of defects which the defence could apply to. This paper aims to determine exactly when and how this defence should apply in Australia, in the context of pharmaceutical product liability claims.

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Objective: To explore the influencing factors of esophageal cancer in the trunk basin of Dawen river , Shandong province. Methods: A case- control study was carried out: 195 living cases of diagnosed esophageal cancer and 195 controls were matched by age and sex and surveyed by a unified inventory. Results: T he following items could rises the risk of esophageal cancer : hard dry diet, smoke homemade cigarettes, alcohol consumption> 500 ml/ day, relatives with tumor in history ( OR = 51850, OR = 161 158, OR = 111 513, OR = 11 827, respectively ) . While drinking tea may have protective effect against esophageal cancer ( OR = 01 311). Conclusion: The high incidence of esophageal cancer in the area is relative not only to the environment and dietary factors, but also to the family history of esophageal cancer.

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Heavy-vehicle driving involves a challenging work environment and a high crash rate. We investigated the associations of sleepiness, sleep disorders, and work environment (including truck characteristics) with the risk of crashing between 2008 and 2011 in the Australian states of New South Wales and Western Australia. We conducted a case-control study of 530 heavy-vehicle drivers who had recently crashed and 517 heavy-vehicle drivers who had not. Drivers' crash histories, truck details, driving schedules, payment rates, sleep patterns, and measures of health were collected. Subjects wore a nasal flow monitor for 1 night to assess for obstructive sleep apnea. Driving schedules that included the period between midnight and 5:59 am were associated with increased likelihood of crashing (odds ratio = 3.42, 95% confidence interval: 2.04, 5.74), as were having an empty load (odds ratio = 2.61, 95% confidence interval: 1.72, 3.97) and being a less experienced driver (odds ratio = 3.25, 95% confidence interval: 2.37, 4.46). Not taking regular breaks and the lack of vehicle safety devices were also associated with increased crash risk. Despite the high prevalence of obstructive sleep apnea, it was not associated with the risk of a heavy-vehicle nonfatal, nonsevere crash. Scheduling of driving to avoid midnight-to-dawn driving and the use of more frequent rest breaks are likely to reduce the risk of heavy-vehicle nonfatal, nonsevere crashes by 2–3 times.

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Rigid lenses, which were originally made from glass (between 1888 and 1940) and later from polymethyl methacrylate or silicone acrylate materials, are uncomfortable to wear and are now seldom fitted to new patients. Contact lenses became a popular mode of ophthalmic refractive error correction following the discovery of the first hydrogel material – hydroxyethyl methacrylate – by Czech chemist Otto Wichterle in 1960. To satisfy the requirements for ocular biocompatibility, contact lenses must be transparent and optically stable (for clear vision), have a low elastic modulus (for good comfort), have a hydrophilic surface (for good wettability), and be permeable to certain metabolites, especially oxygen, to allow for normal corneal metabolism and respiration during lens wear. A major breakthrough in respect of the last of these requirements was the development of silicone hydrogel soft lenses in 1999 and techniques for making the surface hydrophilic. The vast majority of contact lenses distributed worldwide are mass-produced using cast molding, although spin casting is also used. These advanced mass-production techniques have facilitated the frequent disposal of contact lenses, leading to improvements in ocular health and fewer complications. More than one-third of all soft contact lenses sold today are designed to be discarded daily (i.e., ‘daily disposable’ lenses).

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We propose a framework for adaptive security from hard random lattices in the standard model. Our approach borrows from the recent Agrawal-Boneh-Boyen families of lattices, which can admit reliable and punctured trapdoors, respectively used in reality and in simulation. We extend this idea to make the simulation trapdoors cancel not for a specific forgery but on a non-negligible subset of the possible challenges. Conceptually, we build a compactly representable, large family of input-dependent “mixture” lattices, set up with trapdoors that “vanish” for a secret subset which we hope the forger will target. Technically, we tweak the lattice structure to achieve “naturally nice” distributions for arbitrary choices of subset size. The framework is very general. Here we obtain fully secure signatures, and also IBE, that are compact, simple, and elegant.