Spatial Variation of Land Values in the Colombo District, Sri Lanka Using Geographic Information System

Land value mapping is crucial for urban planning and decision-making, particularly as Sri Lanka undergoes rapid urbanisation. This study focuses on the Colombo district and aims to accurately interpret land values and identify their patterns for effective planning. Using Geographic Information Systems (GIS), the research investigates the spatial variation of land values and the factors influencing them and categorises land value bands. Through geospatial analysis, employing inverse distance-weighted analysis and the geometric interval method, the study gathers land value data and analyses spatial patterns. The research outcomes are expected to offer valuable insights for policymakers, urban planners, and stakeholders involved in land management and development in Colombo. The findings will contribute to an improved land evaluation system, enabling informed planning decisions and sustainable regional urban development

A prospective study of repetition of self-harm following deliberate self-poisoning in rural Sri Lanka.

IntroductionRepetition of deliberate self-harm is an important predictor of subsequent suicide. Repetition rates in Asian countries appear to be significantly lower than in western high-income countries. Methodological differences in studies, and the impact of access to means of self-harm with comparatively higher lethality have been suggested as reasons for these reported differences. This prospective study determines the rates and demographic patterns of deliberate self-poisoning (DSP), suicide and repeated deliberate self-harm resulting non-fatal and fatal outcomes in rural Sri Lanka.MethodsDetails of DSP admission in all hospitals (n = 46) and suicides reported to all police stations (n = 28) in a rural district were collected for the years 2011, 2012 and 2013. Demographic details of the cohort of patients admitted to all hospitals in 2011 due to deliberate self-poisoning (N = 4022), were screened to link with patient records and police reports of the successive two years with high sensitivity using a computer program. Then high specificity manual matching of all screened links was performed to identify repetition within 2 years of initial presentation. Life time repetition was assessed in a randomly selected subset of DSP patients (n = 433).ResultsThere were 15,639 DSP admissions, aged more than 9 years, and 1078 suicides during the study period. The incidence of deliberate self-poisoning and suicide in the population within the study area were 248.3/100,000 and 20.7/100,000 respectively, in 2012. Repetition rates at four weeks, one-year and two-years were 1.9% (95% CI 1.5-2.3%), 5.7% (95% CI 5.0-6.4) and 7.9% (95% CI 7.1-8.8) respectively. The median interval between two attempts were 92 (IQR 10-238) and 191 (IQR 29-419.5) days for the one and two-year repetition groups. The majority of patients used the same poison in the repeat attempt. The age and duration of hospital stay of individuals with repetitive events were not significantly different from those who had no repetitive events. The rate of suicide at two years following DSP was 0.7% (95% CI 0.4-0.9%). The reported life time history of deliberate self-harm attempts was 9.5% (95% CI 6.7-12.2%).ConclusionsThe comparatively low rates of repetition in rural Sri Lanka was not explained by higher rates of suicide, access to more lethal means or differences in study methodology

Conservation Priorities for Tree Ferns (Cyatheaceae) in Sri Lanka

Diversity, phytogeography and conservation status of Sri Lankan tree-ferns are discussed in this paper. The family Cyatheaceae is represented by eight taxa (seven species and one doubtful variety) in Sri Lanka with a high rate of endemism of 75%. Apart from Cyathea walkerae and C. gigantea, the other species are restricted to geographically isolated areas in the country with limited population sizes. Fortunately, all Sri Lankan species of Cyathea occur within the protected areas of the wet zone. However, ex situ conservation is limited to C. walkerae and C. crinita at Botanic Gardens in Hakgala. Despite the family being listed in Annex II of CITES, its species have not yet been assessed in Sri Lanka for the Red Listing criteria. Identification of the nature and level of threat to Sri Lankan Cyathea species is therefore a major priority, followed by the monitoring of populations in situ in protected areas in the wet zone. Ex situ conservation of rare species and cultivation of Cyathea species from spores have also been identified as priority areas. A strong programme should be developed with the National Herbarium to explore little known forest patches in the wet zone to enhance our knowledge of Cyathea species in Sri Lanka. Such information will provide a strong basis for preparing a conservation and management plan for tree-ferns in the country

Immune responses to a single dose of the AZD1222/Covishield vaccine in health care workers

Several COVID-19 vaccines have received emergency approval. Here we assess the immunogenicity of a single dose of the AZD1222 vaccine, at one month, in a cohort of health care workers (HCWs) (629 naïve and 26 previously infected). 93.4% of naïve HCWs seroconverted, irrespective of age and gender. Haemagglutination test for antibodies to the receptor binding domain (RBD), surrogate neutralization assay (sVNT) and ex vivo IFNγ ELISpot assays were carried out in a sub-cohort. ACE2 blocking antibodies (measured by sVNT) were detected in 67/69 (97.1%) of naïve HCWs. Antibody levels to the RBD of the wild-type virus were higher than to RBD of B.1.1.7, and titres to B.1.351 were very low. Ex vivo T cell responses were observed in 30.8% to 61.7% in naïve HCWs. Previously infected HCWs, developed significantly higher (p < 0.0001) ACE2 blocking antibodies and antibodies to the RBD for the variants B.1.1.7 and B.1.351. This study shows high seroconversion after one vaccine dose, but also suggests that one vaccine dose may be insufficient to protect against emerging variants