334 research outputs found
Identification of palaeotsunamis using ground penetrating radar, sedimentological and micropaleontological techniques; implications for Sri Lankan tsunami risk
A study of change in human trabecular bone structure with age and during osteoporosis
The objective of this work was to develop new techniques to view trabecular bone three-dimensionally, and to study its structure and the changes that occur with age and in osteoporosis; the methods used included 3D methods in the SEM, laser confocal microscopy, pseudo-holograms and a "continuous motion parallax method". A detailed analysis of trabecular bone from fourth lumbar vertebral bodies used macro-stereophotographs produced by tilting a sample 10°. Models are proposed for both normal and osteoporotic architecture. A quantitative analysis of the lengths of horizontally oriented trabeculae was carried out. A significant decrease in the number of both vertically and horizontally oriented trabeculae was found. The importance of the influence of different developmental patterns on the formation of the normal structure and of the changing vascularisation on osteoporotic structure are emphasised. Two-dimensional fast Fourier transform methods were employed to study changes in the spatial frequency of trabeculae as a function of orientation. A decrease in spatial frequency was observed in both sexes, but in males this was evident only after the mid-sixth decade in the limited sample studied. Contoured power spectra discriminated different trabecular patterns and the intensity mapping of optical density provided volume density information. Templated reverse transformation was used to study individual orientations of trabeculae. Changes in the quality of trabecular bone with age were also investigated using techniques that analyse bone before and after removal of unmineralised matrix. All specimens were less stiff after removal of osteoid; this was more marked in older specimens. Locally defective mineralisation would explain the changed behaviour observed in some old and osteoporotic specimens. Trabecular fracture patterns had a strong relationship to architecture and microstructure. Scanning electron microscopy was used to study trabecular surfaces. An uncoupling between resorption and formation was evident in older specimens. Two resorption patterns responsible for thinning and perforation and removal trabecular elements were identified. Trabecular microfractures were also investigated
The Development of the Ceylon Civil Service 1802-1833.
The development of the Civil Service of Ceylon is closely interconnected with that of the Headman system. This thesis is partly a study of the interrelation between the offices and institutions established by the British and the Headman system. Chapter One deals with the growth of the central and departmental administrative machinery. A chief feature in this growth was a conflict between liberal and authoritarian trends. Chapter Two deals with the provincial and local administrative machinery. Besides displaying the above conflict the European part of this structure as well as the policy of the Government brought about a partial transformation of the office of Headman. Chapter Three deals with administrative development in the Kandyan provinces. Here the disarrangement of the Sinhalese feudal organization was the chief result of the establishment of European offices. Chapters Four and Five examine the internal organization of the Civil Service. The chief factor in the growth of this organization was the need that was felt to satisfy the aspirations of those setting out from England as Civil Servants. Chapter Six examines the forces that were behind the movement for reform and states the problems of reform. The social and political problems associated with an exclusive Civil Service were the chief among them. Chapter Seven examines the nature of the Colebrooke-Cameron reform proposals. The liberalization of the administrative machinery that was recommended by them was the natural corollary to a desire to create a more individualistic and competitive economy and society
Evaluation of Ambient Air Particulate Matter (PM) Concentration in Urban Context and its Public Perception
Urban air pollution has become a global issue and vehicle emissions, rapid industrialization, and urbanization are known to be the main contributing factors for air pollution. Therefore, air quality monitoring is essential for detecting air pollution levels mainly in urban areas. Among the main air pollutants, particulate matters (PM) play major roles as an urban air pollutant. The objectives of this research study were (a) to evaluate and compare the PM2.5 concentration on ambient air in selected locations in Colombo urban area (b) to calculate air quality index (AQI) to identify the pollutant levels of ambient air in selected study sites and (c) to identify the public perception and awareness regarding the PM-related air pollution. In this research, ambient PM2.5 concentrations were measured by ambient fine dust air sampling techniques in selected locations in Colombo urban area representing commercial, construction, and residential sites. Evaluation and comparison of PM2.5 concentration and questionnaire survey were analysed by using suitable statistical approaches and softwares. The comparisons were made with appropriate WHO standards and its related Sri Lankan standards for air quality guidelines. One sample t-test was used to compare the monitored PM2.5 concentration with the standard PM2.5 concentration. One way ANOVA test and Tukey pair wise comparison test were used to evaluate the significant difference between each category. All the statistical analysis was done by using Minitab 18.0 version. SPSS 16.3 version was used to analyse the survey results. Results of the study indicated that residential areas having significantly low concentrations of PM2.5 concentration while both commercial and construction areas having high concentrations of PM2.5 concentration. The highest PM2.5 concentration were 101.08 μɡ/m3 and it was recorded in Maradana area which came under the commercial category. The lowest PM2.5 concentration was recorded in Kotte representing the residential area. There was no any significant difference of PM2.5 concentration between commercial and construction sites mainly including Borella, Maradana, Peliyagoda and Kelaniya areas. In addition, there was a significant difference between PM2.5 concentrations of selected commercial and residential areas and construction and residential areas. PM2.5 concentrations were varied into the range of 17.23 - 101.08 ɥɡ/m3 in commercial and construction areas and 5.68-26.08 ɥɡ/m3 in residential areas. Calculated AQI by using mean PM 2.5 concentration values in air sampling locations indicated that commercial and construction areas consist with moderate air quality level under the AQI category of 51-100 and residential areas consist with good air quality level under the AQI category of 0-51. Public awareness about the PM-related air pollution is considerably low and majority of the people were mentioned that the air quality is not good in Colombo urban area. Approximately half of the interviewed people were affected to the poor air quality and its related health effects. According to public perception, vehicular emission is the main particulate matter emission source in Colombo area.Keywords: Air quality index, Particulate matter, Urban air pollutio
Effect of mulches and cover crops on water status and gas exchange of coconut (Cocos nucifera L.) palms in gravelly soils
Interrelationship between Ambient Air Pollution and Lichen Diversity Urban, Semi-Urban and Rural Landscapes in Ratnapura
Ambient air pollution has become a global issue. Industrialisation and urbanisation are the main contributing factors for air pollution. Therefore, air quality monitoring is essential for detecting air pollution levels in different environmental conditions. However, the development of indirect indicators of air quality is essential for assessing air pollution levels. Lichens have been identified as effective air quality monitors in worldwide. The objective of the study is the evaluation of ambient air pollutant levels and lichen diversity in urban, semi-urban and rural landscapes in the Ratnapura DSD. NO2 and SO2 play major roles as air pollutants and a passive air sampling technique was used to measure air pollutant levels. Lichen diversity was calculated by Simpson and Shannon-Wiener index. Atmospheric purity index was also calculated. DISTLM procedure and PCA analysis were also used for community based analysis. Nine locations in the Ratnapura district were selected representing the urban, semi-urban and rural landscapes. Univariate and multivariate statistical approaches were used for analyzing related to the levels of air pollutants and lichen species composition in each category. The results of this study have detected that urban areas showed significantly higher (p<0.05) NO2 and SO2 levels than semi-urban and the rural areas while rural areas showed the lowest concentrations of NO2 and SO2 levels. There is a decreasing tendency of air pollutants in urban to rural areas. Further study has detected that some urban landscapes have reached an unhealthy level for sensitive groups with NO2 level according to the WHO air quality index. There is a negative relationship between lichen diversity and atmospheric purity index with ambient average NO2 and SO2 concentrations. Analysis of lichen species indicated some lichen species are more vulnerable to air pollution such as Physcia sp, Herpothallon sp, Arthonia sp, Cryptothecia sp, and sterile crust species while some species are tolerant of air pollution such as Graphis sp, Drinaria picta, Leprocaulon sp and some species of Graphidaceae family. Further study has revealed that high lichen diversity could be observed in some urban areas in Ratnapura which reveals more lichen species have survived in high pollution conditions. There is a tendency of lichen species to adapt to high air pollution conditions. The findings of the study revealed that other environmental factors have affected the relationship of air pollutants and changes of community composition of lichen species along a gradient of urban, semi-urban and undisturbed landscapes in Rathnapura.Keywords: Ambient air pollution, Atmospheric purity index, Lichen diversity, Nitrogen dioxide, Sulfur dioxid
A comparative study of water movement in leaf scorch decline attached and healthy coconut palms using lithium a non-radioactive tracer
Deep Learning Methods for Extracting Metaphorical Names of Flowers and Plants
The domain of Botany is rich with metaphorical terms. Those terms play an
important role in the description and identification of flowers and plants.
However, the identification of such terms in discourse is an arduous task. This
leads in some cases to committing errors during translation processes and
lexicographic tasks. The process is even more challenging when it comes to
machine translation, both in the cases of single-word terms and multi-word
terms. One of the recent concerns of Natural Language Processing (NLP)
applications and Machine Translation (MT) technologies is the automatic
identification of metaphor-based words in discourse through Deep Learning (DL).
In this study, we seek to fill this gap through the use of thirteen popular
transformer based models, as well as ChatGPT, and we show that discriminative
models perform better than GPT-3.5 model with our best performer reporting
92.2349% F1 score in metaphoric flower and plant names identification task.Comment: Accepted for SEPLN 202
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