63 resultados para fecal indicator bacteria

em Deakin Research Online - Australia


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Surface water contamination by human faecal wastes is a widespread hazard for human health. Faecal indicator bacteria (FIB) are the most widely used indicators to assess surface water quality but are less-human-specific and have the potential to survive longer and/or occur naturally in tropical areas. In this study, 13 wastewater chemicals (chloride, boron, orthosphophate, detergents as methylene blue active substances, cholesterol, cholestanol, coprostanol, diethylhexyl phthalate, caffeine, acetaminophen, ibuprofen, sucralose and saccharin) were investigated in order to evaluate tracers for human faecal and sewage contamination in tropical urban catchments. Surface water samples were collected at an hourly interval from sampling locations with distinct major land uses: high-density residential, low-density residential, commercial and industrial. Measured concentrations were analysed to investigate the association among indicators and tracers for each land-use category. Better correlations were found between different indicators and tracers in each land-use dataset than in the dataset for all land uses, which shows that land use is an important determinant of drain water quality. Data were further segregated based on the hourly FIB concentrations. There were better correlations between FIB and chemical tracers when FIB concentrations were higher. Therefore, sampling programs must be designed carefully to take the time of sampling and land use into account in order to effectively assess human faecal and sewage contamination in urban catchments. FIB is recommended as the first tier in assessment of surface water quality impairment and chemical tracers as the second tier. Acetaminophen and coprostanol are recommended as chemical tracers for high-density residential areas, while chloride, coprostanol and caffeine are recommended for low-density residential areas.

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Human faecal contamination poses a widespread hazard for human health. In urban areas, sewer leakage may be an important cause of faecal pollution to surface water. Faecal indicator bacteria (FIB) are the most widely used indicators to monitor surface water quality. However, assessing whether a water body is meeting water quality criteria is made difficult by the high variability of FIB concentrations over time. In this study, the variation of FIB concentration in surface water from tropical urban catchments is investigated. Eleven urban sub-catchments were sampled hourly over 24-hr and samples analysed for FIB. It was found that FIB show a diurnal pattern that is characterised by daytime FIB concentrations that are significantly higher than nighttime FIB concentrations. This observed diurnal variation of FIB closely follows that of sewer flows and contrasts with observations in rural streams where FIB concentrations are known to be low in the daytime and high during the night. Field tracer tests provide qualitative evidence of sewage exfiltration and transport to drains via preferential flow paths. The diurnal FIB variation and field tracer tests indicate the likelihood of surface water contamination due to leaking sewers. The results further suggest that contamination of surface-water drains is likely a widespread problem in tropical urban areas due to extensive drainage networks and the persistence of FIB under tropical conditions. Because of FIB variation over time, the time at which samples are collected is important in being able to capture the daily maximum and minimum FIB concentrations. The Kruskal-Wallis test shows that hourly sampling from 04:00 to 07:00 and from 12:00 to 15:00 results in significantly different FIB concentration (minimum and maximum, respectively). Furthermore, the Wilcoxon-Mann-Whitney test shows that sampling at 12:00 and 14:00 results in significantly higher FIB concentrations, while sampling at 05:00 and 04:00 or 05:00 and 06:00 results in significantly lower FIB concentrations, than sampling at other hours of the day.

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The study goals were to determine the relationship between faecal indicator bacteria (FIB), the HF183 marker and land use, and the phylogenetic diversity of HF183 marker sequences in a tropical urban watershed

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Background Changes in the composition of gastrointestinal microbiota by dietary interventions using pro- and prebiotics provide opportunity for improving health and preventing disease. However, the capacity of lupin kernel fiber (LKFibre), a novel legume-derived food ingredient, to act as a prebiotic and modulate the colonic microbiota in humans needed investigation.

Aim of the study The present study aimed to determine the effect of LKFibre on human intestinal microbiota by quantitative fluorescent in situ hybridization (FISH) analysis.

Design A total of 18 free-living healthy males between the ages of 24 and 64 years consumed a control diet and a LKFibre diet (containing an additional 17–30 g/day fiber beyond that of the control—incorporated into daily food items) for 28 days with a 28-day washout period in a single-blind, randomized, crossover dietary intervention design.
Methods Fecal samples were collected for 3 days towards the end of each diet and microbial populations analyzed by FISH analysis using 16S rRNA gene-based oligonucleotide probes targeting total and predominant microbial populations.

Results Significantly higher levels of Bifidobacterium spp. (P = 0.001) and significantly lower levels of the clostridia group of C. ramosum, C. spiroforme and C. cocleatum (P = 0.039) were observed on the LKFibre diet compared with the control. No significant differences between the LKFibre and the control diet were observed for total bacteria, Lactobacillus spp., the Eubacterium spp., the C. histolyticum/C. lituseburense group and the Bacteroides–Prevotella group.
Conclusions Ingestion of LKFibre stimulated colonic bifidobacteria growth, which suggests that this dietary fiber may be considered as a prebiotic and may beneficially contribute to colon health.

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Of all the proteins involved in prokaryotic cell division FtsZ is one of the earliest acting and most widely distributed, being found in all but a few species. We discuss several recent discoveries of FtsZ in eukaryotic cells and the protein’s role in the division of chloroplasts and mitochondria, organelles that are of bacterial origin.

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With its growing share in national economies, the real estate sector has been considered a vital contributor of economic development. Research efforts are needed in order to gain a better comprehension of the national specificities of the real estate sector and to identify its role in economic development. Due to limited comparable data, the economic indicators of real estate sectors are hard to compare between different countries. This paper aims to explore the quantitative interdependence amongst the real estate sector and other industries in developed economies using input-output analysis, and to investigate their significant linkages. Based on the recently published Organisation for Economic Co-operation and Development (OECD) input-output database at constant prices, the analysis focuses on the real estate's escalating role in terms ofshares in gross output, value added and gross national product. With emphasis on the relative role of manufacturing, construction and services inputs, this paper also highlights the strengths of the push and pull of the real estate sector.

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The support for feminism in Australia came not from the scientific field, where there was almost total opposition to it, but from literature, philosophy and the arts. An art museum is an arbiter of taste and a cultural building that points important ideas throughout its lifetime.

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Organisations spend large sums of money to ensure that their electronic shopfront is as attractive, appealing and efficient as any in the real world. But what about dealing with customers? If someone has a query in the real world they would perhaps approach a sales person or telephone the organisation to obtain a response. The electronic equivalent is e-mail. Do organisations pay sufficient attention to this aspect of their electronic shopfront? The study reported here was undertaken to determine the use of e-mail within Australian organisations and, more importantly, organisations' responsiveness to e-mail
queries.

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Analyses of the twenty facet scores for 243 females and 394 males who undertook Form K of the Myers-Briggs Type Indicator (MBTI®) revealed strong and meaningful patterns of relationships with the four preferences. A clear factor structure of four factors emerged which had a few minor cross-loadings. It was found that the facets are distinctive and generally do not correlate with preferences other than those intended. Comparisons with USA evidence revealed patterns that were even clearer in the Australian data. The previously observed differences related to gender (as found in research on Form G) were reproduced using the Form K format. The evidence implies that the robustness of Fonl1 K with an Australian sample has been demonstrated.

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The interaction between probiotic (Enterococcus spp., Lactobacillus spp., and Lactococcus spp.) and enteric (Bacteroides spp., Escherichia coli, and Salmonella spp.) bacteria with respect to menaquinone production was examined. Menaquinones were measured in cell pellets by high-pressure liquid chromatography and the main homologues produced were MIK7–11. The growth of both Bacteroides and E. coli cultured with the 3 probiotics was significantly inhibited with concomitant reduction in menaquinone production. The vitamin K status of humans could be affected by consumption of probiotic dairy foods via the contribution made by gut microflora.

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The nucleotide sequence of the Brachyspira hyodysenteriae ftnA gene, encoding a putative ferritin protein (FtnA), was determined. Analysis of the sequence predicted that this gene encoded a protein of 180 amino acids. RT-PCR and Western blot showed that the ftnA gene was expressed in B. hyodysenteriae, and evidence suggests that FtnA stores iron rather than haem. ftnA was delivered as DNA and recombinant protein vaccines in a mouse model of B. hyodysenteriae infection. Vaccine efficacy was monitored by caecal pathology and quantification of B. hyodysenteriae numbers in the caeca of infected mice by real-time PCR.

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The Genuine Progress Indicator (GPI) is estimated as if nations operate within a closed economy. Therefore, in terms of coverage, the GPI is most analogous to Gross Domestic Product (GDP). Indeed, within the relevant literature, these two indicators are most often contrasted. However, consideration should be given to adapting the GPI, so it has more in common with Gross National Income (GNI). As with GDP, the GPI is concerned only with a particular physical location. Yet, it may be more effective if the GPI was freed from these physical boundaries in a similar manner to GNI. The GPI should be concerned more with the 'ownership' of the costs and benefits associated with economic growth than with the 'location' of those costs and benefits. Those that derive the most benefit from exploitation of the environment are often physically removed from the location of that damage. The GPI does not consider the net consumers of the negative externalities of environmental costs, merely the producers. Currently, however, the structure of the GPI allows a nation to enjoy, without penalty, the benefits of importing goods from countries which bear a disproportionately large cost of environmental degradation. This results in an overstatement of the real progress experienced by the county importing 'dirty goods'. This paper will investigate how certain GPI adjustments may be adapted to overcome this present shortcoming. However, the purpose of this paper is not only to empirically implement this new approach, but also to stimulate debate as to its potential merit.