2,209 research outputs found

    Identifying potential surface water sampling sites for emerging chemical pollutants in Gauteng Province, South Africa

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    Emerging chemical pollutants (ECPs) are defined as new chemicals which do not have a regulatory status, but which may have an adverse effect on human health and the environment. The occurrence and concentrations of ECPs in South African water bodies are largely unknown, so monitoring is required in order to determine the potential threat that these ECPs may pose. Relevant surface water sampling sites in the Gauteng Province of South Africa were identified utilising a geographic information system (GIS). The sites were identified by identifying potential sources of ECPs, including hospitals and clinics, sewage treatment plants, and areas with high population densities or areas that were vulnerable from an environmental point of view. Buffers were drawn around these areas to identify the water sources which have the highest probability of containing ECPs. Areas along the Klip River were identified as having a high likelihood of containing both anthropogenic ECPs and agricultural ECPs. Additionally, sections of the Hennops River were likely to contain anthropogenic ECPs, while the Blesbokspruit area had a high likelihood of containing agricultural ECPs

    Degradation patterns of natural and synthetic textiles on a soil surface during summer and winter seasons studied using ATR-FTIR spectroscopy

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    © 2017 Elsevier B.V. Textiles are a valuable source of forensic evidence and the nature and condition of textiles collected from a crime scene can assist investigators in determining the nature of the death and aid in the identification of the victim. Until now, much of the knowledge of textile degradation in forensic contexts has been based on the visual inspection of material collected from soil environments. The purpose of the current study was to investigate the potential of a more quantitative approach to the understanding of forensic textile degradation through the application of infrared spectroscopy. Degradation patterns of natural and synthetic textile materials as they were subjected to a natural outdoor environment in Australia were investigated. Cotton, polyester and polyester – cotton blend textiles were placed on a soil surface during the summer and winter seasons and were analysed over periods 1 and 1.5 years, respectively, and examined using attenuated total reflectance (ATR) spectroscopy. Statistical analysis of the spectral data obtained for the cotton material correlated with visual degradation and a difference in the onset of degradation between the summer and winter season was revealed. The synthetic material did not show any signs of degradation either visually or statistically throughout the experimental period and highlighted the importance of material type in terms of preservation. The cotton section from the polyester – cotton blend samples was found to behave in a similar manner to that of the 100% cotton samples, however principal component analysis (PCA) demonstrated that the degradation patterns were less distinct in both the summer and winter trial for the blend samples. These findings indicated that the presence of the synthetic material may have inhibited the degradation of the natural material. The use of statistics to analyse the spectral data obtained for textiles of forensic interest provides a better foundation for the interpretation of the data obtained using ATR-FTIR spectroscopy, and has provided insight into textile degradation processes relevant to a soil environment

    Risk factors for delay in symptomatic presentation: a survey of cancer patients

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    Background: Delay in symptomatic presentation leading to advanced stage at diagnosis may contribute to poor cancer survival. To inform public health approaches to promoting early symptomatic presentation, we aimed to identify risk factors for delay in presentation across several cancers. Methods: We surveyed 2371 patients with 15 cancers about nature and duration of symptoms using a postal questionnaire. We calculated relative risks for delay in presentation (time from symptom onset to first presentation >3 months) by cancer, symptoms leading to diagnosis and reasons for putting off going to the doctor, controlling for age, sex and deprivation group. Results: Among 1999 cancer patients reporting symptoms, 21% delayed presentation for >3 months. Delay was associated with greater socioeconomic deprivation but not age or sex. Patients with prostate (44%) and rectal cancer (37%) were most likely to delay and patients with breast cancer least likely to delay (8%). Urinary difficulties, change of bowel habit, systemic symptoms (fatigue, weight loss and loss of appetite) and skin symptoms were all common and associated with delay. Overall, patients with bleeding symptoms were no more likely to delay presentation than patients who did not have bleeding symptoms. However, within the group of patients with bleeding symptoms, there were significant differences in risk of delay by source of bleeding: 35% of patients with rectal bleeding delayed presentation, but only 9% of patients with urinary bleeding. A lump was a common symptom but not associated with delay in presentation. Twenty-eight percent had not recognised their symptoms as serious and this was associated with a doubling in risk of delay. Embarrassment, worry about what the doctor might find, being too busy to go to the doctor and worry about wasting the doctor’s time were also strong risk factors for delay, but were much less commonly reported (<6%). Interpretation: Approaches to promote early presentation should aim to increase awareness of the significance of cancer symptoms and should be designed to work for people of the lowest socioeconomic status. In particular, awareness that rectal bleeding is a possible symptom of cancer should be raised

    Lean Principles in Vertical Farming: A Case Study

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    Vertical farming (VF) has been recognised as an important tool for managing future food security, yet economic viability poses a significant hurdle with the vast majority of farms closing within three years. The application of lean principles poses an opportunity to address inefficiencies, such as significant labour expenditure, but existing literature is yet to consider process improvement methodologies in VF. In this paper, an established framework for lean implementation is applied to an industry case study providing techniques for process improvement. This work is novel and crucial for workflow standardisation and higher profit margins in this emerging sector

    Reading behaviour project report 2016 : ‘Digital Magpies’ - the academic reading habits of undergraduate students

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    Engagement with the Library is essential in delivering a successful student experience. A previous Library Impact Project found that students who use the Library more tend to achieve better academic results. However, analytics from library systems indicate declining book borrowing and electronic resource usage. Are students really reading less? Student academic reading patterns have adapted to the increase in digital resources. As a result they may be “reading smarter’’. Feedback indicates they expect to find and use information quickly, synthesising information from a variety of sources. As part of a commitment to improve retention and completion figures, the Library has initiated a Reading Behaviours project at the University of Salford, focused on the reading habits of undergraduate students. It explores what motivates their academic reading; whether reading patterns vary according to purpose or source, academic discipline, status, or age and what this means for our role in helping students to find resources. In light of findings, how should we tailor classroom training, e-learning and collaboration with academics to support the student journey? Several key issues have emerged during this project:1. Synthesizing information for an academic purpose2. Embedding information literacy as a flexible learning habit3. Supporting students as they adapt to new learning context

    Effects of increase in temperature and open water on transmigration and access to health care by the Nenets reindeer herders in northern Russia

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    Background . The indigenous Nenets reindeer herders in northern Russia annually migrate several hundred kilometers between summer and winter pastures. In the warming climate, ice-rich permafrost and glaciers are being significantly reduced and will eventually disappear from parts of the Arctic. The emergent changes in hydrological cycles have already led to substantial increases in open water that stays unfrozen for longer periods of time. This environmental change has been reported to compromise the nomadic Nenets&#x2019; traditional way of life because the presence of new water in the tundra reduces the Nenets&#x2019; ability to travel by foot, sled, or motor vehicle from the summer transitory tundra campsites in order to access healthcare centers in villages. New water can also impede their access to family and community at other herder camps and in the villages. Although regional and global models predicting hydrologic changes due to climate changes exist, the spatial resolution of these models is too coarse for studying how increases in open water affect health and livelihoods. To anticipate the full health impact of hydrologic changes, the current gap between globally forecasted scenarios and locally forecasted hydrologic scenarios needs to be bridged. Objectives . We studied the effects of the autumn temperature anomalies and increases in open water on health care access and transmigration of reindeer herders on the Kanin Peninsula. Design . Correlational and time series analyses were completed. Methods . The study population consisted of 370 full-time, nomadic reindeer herders. We utilized clinical visit records, studied surface temperature anomalies during autumn migrations, and used remotely sensed imagery to detect water bodies. Spearman correlation was used to measure the relationship between temperature anomalies and the annual arrival of the herders at the Nes clinic for preventive and primary care. Piecewise regression was used to model change in mean autumnal temperature anomalies over time. We also created a water body product to detect inter-annual changes in water area. Results . Correlation between arrivals to the Nes clinic and temperature anomalies during the fall transmigration (1979&#x2013;2011) was r =&#x200A;0.64, p&#x200A;=&#x200A;0.0004; 95% CI (0.31; 0.82). Regression analysis estimated that mean temperature anomalies during the fall migration in September&#x2013;December were stochastically stationary pre-1991 and have been rising significantly (p&#x200A;&#60;&#x200A;0.001) since then. The rate of change was estimated at +0.1351&#x00B0;C/year, SE&#x200A;=&#x200A;0.0328, 95% CI (+0.0694, +0.2007). The amount of detected water fluctuated significantly interannually (620&#x2013;800 km2). Conclusions . Later arrival of freezing temperatures in the autumn followed by the earlier spring thaws and more open water delay transmigration and reduce herders&#x2019; access to health care. The recently observed delays in arrival to the clinic are likely related to the warming trend and to concomitant hydrologic changes

    Continuous heating of a giant X-ray flare on Algol

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    Giant flares can release large amounts of energy within a few days: X-ray emission alone can be up to ten percent of the star's bolometric luminosity. These flares exceed the luminosities of the largest solar flares by many orders of magnitude, which suggests that the underlying physical mechanisms supplying the energy are different from those on the Sun. Magnetic coupling between the components in a binary system or between a young star and an accretion disk has been proposed as a prerequisite for giant flares. Here we report X-ray observations of a giant flare on Algol B, a giant star in an eclipsing binary system. We observed a total X-ray eclipse of the flare, which demonstrates that the plasma was confined to Algol B, and reached a maximum height of 0.6 stellar radii above its surface. The flare occurred around the south pole of Algol B, and energy must have been released continously throughout its life. We conclude that a specific extrastellar environment is not required for the presence of a flare, and that the processes at work are therefore similar to those on the Sun.Comment: Nature, Sept. 2 199
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