68 resultados para Laboratories


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Greywater reuse has become popular in rural and urban communities of Australia. In recent years, the Barwon region of Victoria has been affected by drought and as a result, water restrictions were imposed at different stages. While a water conservation by-law was introduced in February 2003 with overwhelming community support, greywater reuse is still debated among householders, Environment Protection Authority (EPA), local councils, and the water authorities. Higher levels of greywater reuse are needed due to low average rainfall in the region and high water consumption per capita. This paper looks at the position of the different parties that govern greywater reuse and presents the factors that restrain uniform reuse practices. Factors considered include quantity and quality of greywater generated in the Barwon region, current regulatory controls as reviewed through a series of surveys of local councils and water authorities. While the water restrictions resulted in an increased demand for alternative means of watering garden areas, the regulatory conditions were found to be unsettled about greywater reuse, with a wide range of concerns making these authorities unwilling to encourage it.

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Identical single jersey wool knit fabrics produced inconsistent results when tested on the same type of ICI pill box in 4 independence testing laboratories.  The hypothesis formulated to investigate this event was that continued pilling testing in the ICI pill box changes the frictional properties of the cork liners, resulting in the difference pilling ratings.  The aim of this study was to decrease the inconsistencies in the pilling results by replacing the conventional cork lined pill box with a PerspexTM pill box.  The smae or similar pilling results found for several of the knit facots tested in the two difference pill boxes, while for others there were some significant differences found.  In addition, while using the PerspexTM pill box observations of the movement of the pilling tubes during testing provided evidence of greater fabric-to-fabric abrasion, rather the expected high degree of fabric-to-cork abrasion (or fabric-to-PerspexTM) during pilling testing.

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The majority of on-site sewage management systems in Australia fail to perform to expectations. About 60% to 80% of on-site systems reportedly fail to produce acceptable effluent quality, and there is an increaed concern about the risks associated with public health and environmental pollution. In Victoria, a large proportion of septic tank installations have been reported to discharge highly polluted waste to drains and streams. Users, often considered by regulators as operators, have to bear the costs of upgrade/replacement of their old systems to meet stringent water quality guidelines. Some of the common problems include clogging of the disposal fields due to solids and organic overloading and surfacing of highly polluted effluent. Large land application area is subsequently required for irrigating the effluent and/or installation of upgraded disposal fields.
This paper investigates the effectiveness of various types of textile and plastic media, in polishing primary tank effluent, downstream from a typical two-compartment septic tank system. Results to date show that high biochemical oxygen demand removal rates are achieved from the textile and plastic media (up to 86% and 83% respectively). At these removal levels, the performance of a combined conventional septic tank system and plastic/textile filters is comparable to that of an advanced aerated wastewater treatment system. This approach, subject to further investigation, could provide a less costly upgrade.

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Recently, a family was denied the right to subdivide their four-hectare property on the outskirts of Melbourne, Victoria into nine residential allotments ranging in size from 4000 m2 to 6600 m2. Unsuccessful applications and approaches in the past, prior to our commissioning in late 2003, had been rejected on the basis of assessments of poor land capability, onerous wet weather storage requirements and a curious 60 m buffer from a nearby intermittent watercourse. Restriction on the type of interim wastewater systems deemed suitable for five allotments was also a major issue. The site did not have mains power and had no sewer connections. The water authority and Victorian Civil and Administrative Tribunal (V CAT) order, prior to commissioning of the authors, asserted that "reticulated sewer is the preferred infrastructure for the area under investigation". However, the requirements imposed followed the letter of the guidelines rather than the principles. Various professional reports had already been produced on behalf of both the client and the regulator. A review of these indicated that the project had not been assessed in accordance with standard practices, had unusually restrictive assumptions, and did not accord with government policies on ecologically sustainable development.
The paper highlights the importance of sustaining professional and ethical practices to avoid costly litigation. Some professionals may have been in breach of the Institution of Engineers' Code of Ethics; others may have been in need of professional development. The question also arises whether the regulator had sought to use these adverse reports in order to satisfy unrelated planning issues.
While the writers managed to succeed in convincing the VCAT that these restrictions were unnecessary, the client ultimately had to comply with the regulator's wishes because of financial pressures. This unnecessary regimentation raises the issue of how best to safeguard lay people of moderate means against the practices of professional people who know or should know better.

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Objective: A study aimed at exploring the variation in perceptions of learning outcomes reported by undergraduate nursing students enrolled in a problem-based learning subject in a pre-registration Bachelor of Nursing course (BN).
Method: Students were asked to respond to four open-ended questions which focussed on their learning outcomes in the different teaching/learning modalities of the subject. Data were analysed in two phases using a modified phenomenographic analysis. In the first phase a set of categories of description were developed from the student responses to questions related to the learning modalities. In the second phase the individual responses were classified in terms of the categories. Finally, correlations between the learning modalities were identified. In this paper the approach to analysis, the process of category identification and the correlations between the learning modalities will be described and the implications for further research and teaching will be discussed.
Results: The findings indicated that there were two distinct groups of student responses. Inward focussed students who described outcomes in terms of their own learning and students whose focus was outward i.e. describing learning in terms of patient care and how learning relates to that care. Another important result shows the relationship between the learning modalities and outcomes. From the students' perspective, the most sophisticated outcomes of the lectures and laboratories were ideas and skills to be used and applied in clinical settings. Whereas, the group-based activities in which clinical problems were presented to the students in the form of Situation Improvement Packages (SIPS) focussed their attention on the clinical setting which constituted a preparation for the realities of clinical practice.
Conclusion: The findings from this study indicate that students perceive their learning in the group based teaching/learning modality (SIPS) as effective in focussing them on the reality of their role in the clinical practice environment while lectures and laboratories provided the skills and knowledge required for this setting.

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Objective: To describe the epidemiological and microbiological characteristics and notification patterns of invasive meningococcal disease (IMD) in Victoria between 1990 and 1999.

Methods: Cases of IMD occurring between 1990 and 1995 identified in any of three databases were combined, matching where possible. Statistical modelling provided estimates of cases missing from all datasets. Notification sources for 1999 and 2000 cases were identified. Cases identified from notification and laboratory results provided the data to describe IMD epidemiology between 1990 and 1999.

Results: Between 1990 and 1995, 479 cases of IMD were identified. Three individual datasets each identified between 62 and 82% of cases and 47% of cases were identified in all three datasets. Statistical modelling estimated that between 37 and 83 additional cases were not identified by any dataset. Serogroup B and C strains caused 63 and 33% of culture-positive cases, respectively, with a substantial rise in serogroup C cases in 1999. Epidemiological characteristics remained relatively constant between 1990 and 1998, but an increase in patient age was seen in cases with serogroup C disease in 1999. In addition to three clonal strains seen elsewhere, an additional strain was identified that was unique to Victoria. Since January 1999, only 72% of notifications have come from treating doctors.

Conclusions: Meningococcal disease is of increasing public health significance in Victoria. Laboratory enhanced notification has improved case identification and detailed microbiological information has improved our understanding of the changing epidemiology of this disease. Collaboration with laboratories and other agencies, active investigation of putative cases and microbiological monitoring are important elements in supporting public health decisions about the control of IMD.

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Creatine (Cr) plays a key role in cellular energy metabolism and is found at high concentrations in metabolically active cells such as skeletal muscle and neurons. These, and a variety of other cells, take up Cr from the extra cellular fluid by a high affinity Na+/Cl--dependent creatine transporter (CrT). Mutations in the crt gene, found in several patients, lead to severe retardation of speech and mental development, accompanied by the absence of Cr in the brain.
In order to characterize CrT protein(s) on a biochemical level, antibodies were raised against synthetic peptides derived from the N- and C-terminal cDNA sequences of the putative CrT-1 protein. In total homogenates of various tissues, both antibodies, directed against these different epitopes, recognize the same two major polypetides on Western blots with apparent Mr of 70 and 55 kDa. The C-terminal CrT antibody (α-CrTCOOH) immunologically reacts with proteins located at the inner membrane of mitochondria as determined by immuno-electron microscopy, as well as by subfractionation of mitochondria. Cr-uptake experiments with isolated mitochondria showed these organelles were able to transport Cr via a sulfhydryl-reagent-sensitive transporter that could be blocked by anti-CrT antibodies when the outer mitochondrial membrane was permeabilized. We concluded that mitochondria are able to specifically take-up Cr from the cytosol, via a low-affinity CrT, and that the above polypeptides would likely represent mitochondrial CrT(s). However, by mass spectrometry techniques, the immunologically reactive proteins, detected by our anti-CrT antibodies, were identified as E2 components of the agr-keto acid dehydrogenase multi enzyme complexes, namely pyruvate dehydrogenase (PDH), branched chain keto acid dehydrogenase (BC-KADH) and α-ketoglutarate dehydrogenase (α-KGDH). The E2 components of PDH are membrane associated, whilst it would be expected that a mitochondrial CrT would be a transmembrane protein. Results of phase partitioning by Triton X-114, as well as washing of mitochondrial membranes at basic pH, support that these immunologically cross-reactive proteins are, as expected for E2 components, membrane associated rather than transmembrane. On the other hand, the fact that mitochondrial Cr uptake into intact mitoplast could be blocked by our α-CrTCOOH antibodies, indicate that our antisera contain antibodies reactive to proteins involved in mitochondrial transport of Cr. The presence of specific antibodies against CrT is also supported by results from plasma membrane vesicles isolated from human and rat skeletal muscle, where both 55 and 70 kDa polypeptides disappeared and a single polypeptide with an apparent electrophoretic mobility of ~ 60 kDa was enriched This latter is most likely representing the genuine plasma membrane CrT.
Due to the fact that all anti-CrT antibodies that were independently prepared by several laboratories seem to cross-react with non-CrT polypeptides, specifically with E2 components of mitochondrial dehydrogenases, further research is required to characterise on a biochemical/biophysical level the CrT polypeptides, e.g. to determine whether the ~ 60 kDa polypeptide is indeed a bona-fide CrT and to identify the mitochondrial transporter that is able to facilitate Cr-uptake into these organelles. Therefore, the anti-CrT antibodies available so far should only be used with these precautions in mind. This holds especially true for quantitation of CrT polypeptides by Western blots, e.g. when trying to answer whether CrT's are up- or down-regulated by certain experimental interventions or under pathological conditions.
In conclusion, we still hold to the scheme that besides the high-affinity and high-efficiency plasmalemma CrT there exists an additional low affinity high Km Cr uptake mechanism in mitochondria. However, the exact biochemical nature of this mitochondrial creatine transport, still remains elusive. Finally, similar to the creatine kinase (CK) isoenzymes, which are specifically located at different cellular compartments, also the substrates of CK are compartmentalized in cytosolic and mitochondrial pools. This is in line with 14C-Cr-isotope tracer studies and a number of [31P]-NMR magnetization transfer studies, as well as with recent [1H]-NMR spectroscopy data.

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This mini review highlights the synthesis and photophysical evaluation of anion sensors, for nonaqueous solutions, that have been developed in our laboratories over the last few years. We have focused our research mainly on developing fluorescent photoinduced electron transfer (PET) sensors based on the fluorophore-spacer-anion receptor principle using several anthracene (emitting in the blue) and 1,8-naphthalimide (emitting in the green) fluorophores, with the aim of targeting biologically and industrially relevant anions such as acetates, phosphate and amino acids, as well as halides such as fluoride. The receptors and the fluorophore are separated by a short methyl or ethyl spacer, where the charge neutral anion receptors are either aliphatic or aromatic urea (or thiourea) moieties. For these, the anion recognition is through hydrogen bonding, yielding anion:receptor complexes. Such bonding gives rise to enhanced reduction potential in the receptor moieties which causes enhancement in the rate of PET quenching of the fluorophore excited state from the anion:receptor moiety. This design can be further elaborated on by incorporating either two fluorophores, or urea/thiourea receptors into the sensor structures, using anthracene as a fluorophore. For the latter design, the sensors were designed to achieve sensing of bis-anions, such as di-carboxylates or pyrophosphate, where the anion bridged the anthracene moiety. In the case of the naphthalimide based mono-receptor based PET sensors, it was discovered that in DMSO the sensors were also susceptible to deprotonation by anions such as F− at high concentrations. This led to substantial changes in the absorption spectra of these sensors, where the solution changed colour from yellow/green to deep blue, which was clearly visible to the naked eye. Hence, some of the examples presented can act as dual fluorescent-colorimetric sensors for anions. Further investigations into this phenomenon led to the development of simple colorimetric sensors for fluorides, which upon exposure to air, were shown to fix carbon dioxide as bicarbonate.

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This review article focuses primarily on the work carried in our laboratories over the last few years using luminescent and colorimetric sensors, where the anion recognition occurs through hydrogen bonding in organic or aqueous solvents. This review begins with the story of the discovery of fluorescent photoinduced electron transfer (PET) sensors for anions using charged neutral urea or thiourea receptors where both fluorescent and NMR spectroscopic methods monitored anion recognition. This work led to the development of dual luminescent and colorimetric anion sensors based on the use of the ICT based naphthalimide chromophore, where ions such as fluoride gave rise to changes in both the fluorescence and the absorption spectra of the sensors, but at different concentrations. Here, the former changes were due to hydrogen bonding interactions, whereas the latter was due to the deprotonation of acidic protons, giving rise to the formation of the bifluoride anion (HF2−). Modification of the 4-amino-l,8-naphthalimide moiety has facilitated the formation of colorimetric anion sensors that work both in organic or aqueous solutions. Such charge neutral receptor motifs have also been incorporated into organic scaffolds with norbomyl and calixarene backbones, which have enabled us to produce anion directed self-assembled structures.

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This paper considers the provision of laboratory-practicals for distance-education students in engineering degree programmes. The authors discuss the role of laboratory-practical work in the curriculum and reflect on five methods that can be used to ensure off-campus students have an equivalent practical experience as the traditional on-campus cohort. On-campus sessions, videotapes (or ‘on-line’ movie-clips), computer simulations, home experiment kits and laboratories controlled over the internet are covered. Some examples are given to show how these can be incorporated into the curriculum. A case study then discusses the problem of (and an exemplar solution to) delivering the laboratory-practical components of two microcontroller units offered at Deakin University – a leading provider of distance-education in Australia. In doing so, it leads the reader through the solution process and cites some constraints that drive the choice of model - for example, cost considerations and the need for relevant didactic materials.

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Over the past 10 years or so, confidence intervals have become increasingly recognised in program evaluation and quantitative health measurement generally as the preferred way of reporting the accuracy of statistical estimates. Statisticians have found that the more traditional ways of reporting results - using P-values and hypothesis tests - are often very difficult to interpret and can be misleading. This is particularly the case when sample sizes are small and results are 'negative' (ie P>0.05); in these cases, a confidence interval can communicate much more information about the sample and, by inference, about the population. Despite this trend among statisticians and health promotion evaluators towards the use of confidence intervals, it is surprisingly difficult to find succinct and reasonably simple methods to actually compute a confidence interval. This is particularly the case for proportions or percentages. Much of the data which are analysed in health promotion are binary or categorical, rather than the quantities and continuous variables often found in laboratories or other branches of science, so there is a need for health promotion evaluators to be able to present confidence intervals for percentages or proportions. However, the most popular statistical analysis computer package among health promotion professionals, SPSS does not have a routine to compute a simple confidence interval for a proportion! To address this shortcoming, I present in this paper some fairly simple strategies for computing confidence intervals for population percentages, both manually and using the right computer software.

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• 1. The present review discusses the potential role of nitric oxide (NO) in the: (i) regulation of skeletal muscle glucose uptake during exercise; and (ii) activation of mitochondrial biogenesis after exercise.
• 2. We have shown in humans that local infusion of an NO synthase inhibitor during exercise attenuates increases in skeletal muscle glucose uptake without affecting blood flow. Recent studies from our laboratory in rodents support these findings in humans, although rodent studies from other laboratories have yielded conflicting results.
• 3. There is clear evidence that NO increases mitochondrial biogenesis in non-contracting cells and that NO influences basal skeletal muscle mitochondrial biogenesis. However, there have been few studies examining the potential role of NO in the activation of mitochondrial biogenesis following an acute bout of exercise or in response to exercise training. Early indications are that NO is not involved in regulating the increase in mitochondrial biogenesis that occurs in response to exercise.
• 4. Exercise is considered the best prevention and treatment option for diabetes, but unfortunately many people with diabetes do not or cannot exercise regularly. Alternative therapies are therefore critical to effectively manage diabetes. If skeletal muscle NO is found to play an important role in regulating glucose uptake and/or mitochondrial biogenesis, pharmaceutical agents designed to mimic these effects of exercise may improve glycaemic control.

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Objective : To document the types of, and mortality from, Staphylococcus aureus bacteraemia in Australia and New Zealand, and determine factors associated with mortality.

Design and setting : Prospective observational study in 27 independent or hospital pathology laboratories in Australia (24) and New Zealand (3), employing a web-based database to prospectively record demographic features, selected risk factors, principal antibiotic treatment and mortality data on all patients with positive blood cultures for S. aureus from June 2007 to May 2008.

Main outcome measure : 30-day all-cause mortality.

Results : 1994 episodes of S. aureus bacteraemia were identified, and complete 30-day follow-up data were available for 1865. Most episodes had their onset in the community (60.8%; 95% CI, 58.7%–63.0%). Methicillin-resistant S. aureus (MRSA) caused 450 episodes (24.1%; 95% CI, 22.2%–25.9%), and 123 of these (27.3%) had a susceptibility profile consistent with community-associated MRSA. All-cause mortality at 30 days was 20.6% (95% CI, 18.8%–22.5%). On univariate analysis, increased mortality was significantly associated with older age, European ethnicity, MRSA infection, infections not originating from a medical device, sepsis syndrome, pneumonia/empyema, and treatment with a glycopeptide or other non-β-lactam antibiotic. On multivariable analysis, independent predictors of mortality were age, sepsis syndrome, pneumonia/empyema, device-associated infection with a secondary focus, left-sided endocarditis, and treatment with a glycopeptide such as vancomycin, but not MRSA infection.

Conclusions : S. aureus bacteraemia is a common infection in both the community and hospitals in Australia and New Zealand, and is associated with appreciable mortality. Invasive MRSA infection may be more life-threatening, partly because of the inferior efficacy of the standard treatment, vancomycin. National web-based surveillance of S. aureus bacteraemia and its outcomes is not only important but also easily achievable.

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Although it is known that many birds possess ultraviolet (UV)-sensitive vision, most commercially housed poultry species, as well as species held in zoos, laboratories, or bred for show, are maintained under lighting that is deficient in UV wavelengths compared with normal daylight. UV-sensitive vision has been shown to be important in both foraging and mate-choice decisions. UV-poor conditions, in which information in this waveband is eliminated, could, therefore, present an important welfare issue. Eight European starlings were given a series of preference tests (eight hours per trial, for six days), in which they could choose to feed in one of four channels. Four experimental trials were carried out, during which the channels were covered in either UV-transmitting (UV+) or UV-blocking (UV-) filters, to determine whether birds had an initial preference for feeding in UV-rich environments and whether there was any change in their preference over time. There was an initial preference for the UV+ environment, but this preference declined very rapidly with familiarity, and was absent by the final trial. These results imply that starlings can rapidly adjust their feeding behaviour if faced with unfamiliar light environments and that any initial behavioural changes attributable to UV-deficient environments may be short-lived. However, further work is necessary to establish whether these adjustments occur across a range of species and contexts before any welfare concerns can be ruled out.