Lichens as a biomonitoring tool for detecting heavy metal air pollution associated with industrial activities in Collie, south-western Australia

During the last few decades, various techniques for using lichens as biomonitors have been developed for monitoring air pollution and forest ecosystem health. Lichens have been used effectively to determine the dispersion of heavy metals emitted by industrial point-sources; however the approach has not been commonly used in Australia. This thesis aimed to determine the effectiveness of using a lichen biomonitoring approach to measure the heavy metal pollutants emitted from coal-fired power stations and related industries in Collie, south-western Australia, an area with concern over poor air quality. Three different approaches to lichen biomonitoring were investigated. The first explored lichen community composition patterns in thirty-six study sites across an identified pollution gradient in the jarrah forest ecosystems of Collie. The second measured in situ Usnea inermis lichens for heavy metals, across wet and dry seasons in Collie. The third approach used lichen transplant bags of Usnea inermis to determine seasonal heavy metal accumulation patterns. Because the gaseous pollutants NO2 and SO2 are known to have a significant effect on lichen vitality and distribution, they were monitored by means of a direct measurement approach using Radiello® passive air samplers, to determine any confounding effects. A total of twenty lichen taxa were recorded in the lichen community study, with an average species diversity of ten per site. The lichens Usnea inermis and Cladonia rigida occurred at all thirty-six study sites. High lichen diversity and abundance values were recorded from control sites, and crustose and squamulose species were more abundant across all study sites. The grouping of lichen communities into pollution-tolerant classes, based on information from other studies, showed that the jarrah forests surrounding the industries in Collie were dominated by pollution-tolerant lichen species, while sensitive species were infrequent and rare. Spatial distribution maps of lichen diversity indices showed areas with low diversity values downwind from the coal mines and coal-fired power stations and near an alumina refinery, indicating a possible influence from these point-sources on lichen community composition. Pollution effects on lichen communities were observed with little influence from forest management practices, demonstrating the effectiveness of this method for monitoring air pollution influences in managed jarrah forests. The study also identified Usnea inermis as a suitable species for both the in situ and transplant lichen biomonitoring experiments to explore heavy metal pollution in the area, because of its widespread distribution across the pollution gradient. Low concentrations of NO2 and SO2 were recorded by Radiello® passive samplers, suggesting that these pollutants had very little confounding influence on lichen community composition and heavy metal accumulation patterns. However, seasonal differences in the dispersion of gaseous pollutants were observed, particularly in the summer season. The areas influenced by gaseous pollutants were also found to be those with low lichen diversity, suggesting that although low in concentration, the gaseous pollutants were having a demonstrable influence on the lichens in the jarrah forests in Collie. Mean concentrations for the metals As, Cd, Cr, Cu, Pb, Mn, Hg, Ni and Zn were low for in situ Usnea inermis lichens; however elevated concentrations of some metals were recorded at certain locations. Arsenic concentrations in spring were high from sites close to the coal mines and Mn was elevated in both seasons from sites near an alumina refinery. Higher metal concentrations were recorded in the higher rainfall autumn season compared with spring for most metals. The fallout patterns of heavy metals were explained by a power curve showing exponential decreases in concentrations, with very low concentrations found beyond the 8 - 10 km distance range from the closest pollution source. Spatial dispersion maps showed interpolated concentrations consistent with that expected if point-sources were responsible for the generation of high atmospheric heavy metal concentrations. Transplanted Usnea inermis lichens did not show elevated metal concentrations, however seasonal variations were observed, with the highest concentrations recorded in the wet winter season. Metal uptake in both the in situ and transplanted lichen studies was favoured by low temperature and high rainfall, suggesting that metal uptake was promoted during periods of wet deposition. This highlights the importance of season of sampling if lichen biomonitoring studies are to be deployed in WA. The wetter and cooler winter season with more consistent rainfall patterns is recommended as optimal for conducting lichen biomonitoring studies in Collie. The transplants exposed over a 48 week period recorded the highest concentrations for most metals, however they also showed a loss of metal accumulation ability at the high exposure sites. Exposure periods of 24 – 32 weeks (6 – 8 months) are recommended for more reliable results when using lichen transplants. The transplant study also identified that the control sites were affected by industrial emissions, suggesting that reference sites should be located at distances greater than those used in this study. The results from all three biomonitoring approaches identified pollution dispersion patterns associated with industrial point-sources, and also identified a pollution influence at the control sites, an area previously considered to be unaffected by industrial pollution. Findings from this study support the idea that a lichen biomonitoring approach can be used as an effective tool for monitoring heavy metal air pollution in Western Australia and if used correctly it could replace the more expensive active sampling techniques. The study also provided essential baseline information for future studies on the effect of industrial pollution on lichen communities in WA

A simple cleaning machine for mattress fibre

A simple low cost cleaning machine for mattree fibre was designed and manufactured by the coconut processing board in order to get rid of dust in dry mattree fibre. This machine is described with tables ro indicate how the particular design came to be considered the most suitable for the purpose. The conditions under which it should be operated to give the best results are indicated

Severe Dengue Epidemics in Sri Lanka, 2003–2006

One-sentence summary for table of contents: Changes in transmission dynamics and virus genes are likely increasing emergence of severe epidemics in this country

Emergence and Global Spread of a Dengue Serotype 3, Subtype III Virus

Over the past two decades, dengue virus serotype 3 (DENV-3) has caused unexpected epidemics of dengue hemorrhagic fever (DHF) in Sri Lanka, East Africa, and Latin America. We used a phylogenetic approach to evaluate the roles of virus evolution and transport in the emergence of these outbreaks. Isolates from these geographically distant epidemics are closely related and belong to DENV-3, subtype III, which originated in the Indian subcontinent. The emergence of DHF in Sri Lanka in 1989 correlated with the appearance there of a new DENV-3, subtype III variant. This variant likely spread from the Indian subcontinent into Africa in the 1980s and from Africa into Latin America in the mid-1990s. DENV-3, subtype III isolates from mild and severe disease outbreaks formed genetically distinct groups, which suggests a role for viral genetics in DHF

Epidemiology of dengue in Sri Lanka before and after the emergence of epidemic dengue hemorrhagic fever.

Before 1989, dengue epidemiology in Sri Lanka was characterized by frequent transmission of all four dengue serotypes but a low incidence of dengue hemorrhagic fever (DHF). After 1989, cases of DHF dramatically increased. Here we present the results of epidemiologic studies conducted in Colombo, Sri Lanka before and after epidemic emergence of DHF in 1989. We compared the proportion of dengue cases among people with fever attending clinics from 1980 to 1984 and in 1997 and 1998 to determine if an increase in dengue transmission was associated with more DHF cases being reported. We also compared the relative distribution of dengue virus serotypes circulating in Colombo before and after the emergence of DHF. We detected no significant differences in dengue as a proportion of fever cases or in serotype distribution between the pre and post-DHF periods. We conclude that an increase in virus transmission or a change in circulating serotypes does not explain the epidemic emergence of DHF in Sri Lanka

Evidence and rationale for the World Health Organization recommended standards for Japanese encephalitis surveillance

<p>Abstract</p> <p>Background</p> <p>Japanese encephalitis (JE) is the most important form of viral encephalitis in Asia. Surveillance for the disease in many countries has been limited. To improve collection of accurate surveillance data in order to increase understanding of the full impact of JE and monitor control programs, World Health Organization (WHO) Recommended Standards for JE Surveillance have been developed. To aid acceptance of the Standards, we describe the process of development, provide the supporting evidence, and explain the rationale for the recommendations made in the document.</p> <p>Methods</p> <p>A JE Core Working Group was formed in 2002 and worked on development of JE surveillance standards. A series of questions on specific topics was initially developed. A literature review was undertaken and the findings were discussed and documented. The group then prepared a draft document, with emphasis placed on the feasibility of implementation in Asian countries. A field test version of the Standards was published by WHO in January 2006. Feedback was then sought from countries that piloted the Standards and from public health professionals in forums and individual meetings to modify the Standards accordingly.</p> <p>Results</p> <p>After revisions, a final version of the JE surveillance standards was published in August 2008. The supporting information is presented here together with explanations of the rationale and levels of evidence for specific recommendations.</p> <p>Conclusion</p> <p>Provision of the supporting evidence and rationale should help to facilitate successful implementation of the JE surveillance standards in JE-endemic countries which will in turn enable better understanding of disease burden and the impact of control programs.</p

LEARN: A multi-centre, cross-sectional evaluation of Urology teaching in UK medical schools

OBJECTIVE: To evaluate the status of UK undergraduate urology teaching against the British Association of Urological Surgeons (BAUS) Undergraduate Syllabus for Urology. Secondary objectives included evaluating the type and quantity of teaching provided, the reported performance rate of General Medical Council (GMC)-mandated urological procedures, and the proportion of undergraduates considering urology as a career. MATERIALS AND METHODS: LEARN was a national multicentre cross-sectional study. Year 2 to Year 5 medical students and FY1 doctors were invited to complete a survey between 3rd October and 20th December 2020, retrospectively assessing the urology teaching received to date. Results are reported according to the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). RESULTS: 7,063/8,346 (84.6%) responses from all 39 UK medical schools were included; 1,127/7,063 (16.0%) were from Foundation Year (FY) 1 doctors, who reported that the most frequently taught topics in undergraduate training were on urinary tract infection (96.5%), acute kidney injury (95.9%) and haematuria (94.4%). The most infrequently taught topics were male urinary incontinence (59.4%), male infertility (52.4%) and erectile dysfunction (43.8%). Male and female catheterisation on patients as undergraduates was performed by 92.1% and 73.0% of FY1 doctors respectively, and 16.9% had considered a career in urology. Theory based teaching was mainly prevalent in the early years of medical school, with clinical skills teaching, and clinical placements in the later years of medical school. 20.1% of FY1 doctors reported no undergraduate clinical attachment in urology. CONCLUSION: LEARN is the largest ever evaluation of undergraduate urology teaching. In the UK, teaching seemed satisfactory as evaluated by the BAUS undergraduate syllabus. However, many students report having no clinical attachments in Urology and some newly qualified doctors report never having inserted a catheter, which is a GMC mandated requirement. We recommend a greater emphasis on undergraduate clinical exposure to urology and stricter adherence to GMC mandated procedures