PURSE 2013

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A case series of treatable causes of bronchiectasis
(The University of Peradeniya, 2013-07-04) Siribaddana, A.; Wickramasekara, K.; Illeperuma, S. K.; Punyajjeva, U. A. G.; Pathirana, G. G. P.
Bronchiectasis is a chronic inflammatory lung disease which leads to permanent lung damage and significant morbidity. The underlying causes of bronchiectasis vary and in Sri Lanka the incidence of bronchiectasis and its causes are not known. This study was conducted to identify the patients with correctable causes of bronchiectasis who responded to appropriate therapy. Patients who presented with symptoms of bronchiectasis, to the respiratory unit 1, Teaching Hospital Kandy from October 2010 to December 2010, were investigated. Informed consent was taken from the patients before the clinical details were obtained. In all patients, except a child, the diagnosis of bronchiectasis was confirmed by High Resolution Computed Tomography of the chest. Chest X-ray was used to confirm the diagnosis in the child. All patients were investigated with full blood counts, X ray sinuses, serum proteins, serum immunoglobulin levels, sputum direct smears, culture for mycobacteria and skin prick tests for aspergillosis. Those with positive skin tests underwent antibody testing for Aspergillosis. Those who were diagnosed to have post tuberculosis bronchiectasis and concurrent pulmonary tuberculosis were excluded. There were 26 cases with a mean age of 31 years (range 8 to 56 years). 7 (27%) were found to have a correctable cause, which included, 4 cases of allergic broncho-pulmonary aspergillosis, 1 common variable hypogammaglobulinaemia, 1 relapsing polychondritis, and 1 case of myelodysplastic syndrome associated with leucopaenia. These patients were put on specific treatment which resulted in significant improvement in their symptoms and quality of life. Some patients were completely asymptomatic after specific therapy. We conclude that investigation for an underlying cause should be done in all patients diagnosed to have bronchiectasis.
A case study to explore whether teachers use their computer literacy to enhance the effectiveness of teaching in secondary level classes
(The University of Peradeniya, 2013-07-04) Dawatawaththa, V. N.; Jayawardena, S. K. R.; Kallora, E. M. U. K.; Kandegedara, A. P.; Wanigasekara, W. S. M. B. S.; Ekanayake, T. M. S. S. K. Y.
It is recognized that Information Communication Technologies (ICT) have the potential to enhance the teaching process in various ways. Recognizing these potentials the Ministry of Education (MOE) initiated a number of programs to develop teachers’ computer literacy. For instance, during the last five years a large number of teachers were given a chance to attend trainings in computer technology such as Computer Assisted Learning (CAL), International Computer Driving License (ICDL), International Pedagogical Information and Communication Technology (IPICT) and Intel. The aim of this research is to evaluate the extent to which the teachers used their computer literacy and skills they acquired from CAL, ICDL, IPICT programs in their teachings of compulsory subjects such as English, Mathematics, Science, Sinhala, Buddhism and History in secondary level education. The mixed methods approach was used in this study. Eighteen teachers out of 15722 who followed the above mentioned computer trainings and who teach in the Kandy district were selected as the sample for this study. These 18 teachers represented different types of schools (Type 1 AB, 1 C, 2). First, the teachers were given a questionnaire and based on their answers further information was collected through semi-structured interviews. The data from the questionnaires were analysed using MS Excel and they were shown in ratios and percentages. The data gathered at interviews were transcribed and analysed using the thematic analysis technique. The findings of the study indicated that all teachers in the sample who taught Science and English integrated ICT into their teaching. Furthermore, only 33% of teachers who taught Mathematics and Sinhala used ICT in their teaching process. However, none of the teachers who taught Buddhism or History had integrated ICT into their teaching. Moreover, it was identified that a number of factors minimized the use of ICT by teachers in their teaching. The student - computer ratio is low in most of the schools. Furthermore, only 1 AB and 1C schools had internet facilities. According to the findings of the survey 94.44% of teachers had a positive attitude towards the use of computers in teaching and learning. Yet, only 72.22% used computers for their teaching. The study has further revealed that the lack of adequate time (33.35%), not having adequate computer knowledge (5.55%), lapses in the training provided by the Department of Education and the lack of proper supervision or feedback decreased ICT integration into teaching. However, this study has a limitation on generalizing the results as only 0.1% of the teachers who underwent the training were used as the sample.
A comparison of health habits, cancer risk and the use of screening tests for cancer between a migrant Sri Lankan population in the USA and their siblings/first cousins living in Sri Lanka
(The University of Peradeniya, 2013-07-04) Dissanayake, D. S.; Jones, L. A.
Comparing a migrant population with that of siblings and first cousins still living in the country of origin could explain how health habits have changed with acculturation to a new society. Cancer is the second leading cause of death in Sri Lanka. The aims of this study were to compare the health habits and other factors related to cancer, and the pattern of utilization of methods available for early detection of cancer, between Sri Lankan Sinhalese living in Houston, United States of America (USA) with that of their siblings and first cousins living in Sri Lanka. This cross sectional comparative study comprised Sri Lankan Sinhalese adults living in Houston, USA and their adult siblings and first cousins living in Sri Lanka. The 90 pairs studied were matched for sex and for age within ± 10 years. Data collection was carried out as telephone interviews using a questionnaire. Engaging in physical exercise was significantly lower among the subjects living in Sri Lanka (p=0.003). Having less than thirty minutes of moderate to vigorous physical exercise was reported by 41% of the group in Sri Lanka and 19% of the group in the USA. When compared to the study group in Sri Lanka, alcohol consumption was significantly higher in the USA group (p=0.006). Only 4% of the USA group and 5.5% of the group in Sri Lanka were heavy smokers. Frequent ‘bulath’ chewing with carcinogenic ingredients was reported among only those living in Sri Lanka (4%). A significantly higher percentage of the USA subjects had a high consumption of red meat (51%) compared to relatives in Sri Lanka (10%) (p< 0.001). Fruit and fruit juice intake was higher among US participants (p= 0.008, p< 0.001 respectively). Fish and vegetable consumption was higher among the participants in Sri Lanka (p< 0.001, p= 0.004 respectively). Type 2 diabetes mellitus was reported by 18% of participants from each country. Equally high proportions from both countries (73% in the USA and 72% in Sri Lanka) perceived as having moderate to high mental stress. Of the females aged 35 years or above (84% in USA and 11.9% in Sri Lanka) have been screened for breast cancer by a mammogram (p<0.001). The difference is highly significant. A significantly higher proportion of females living in the USA have been screened for pre-malignant lesions of the cervix by a Pap smear (p<0.001). Of the males aged over 50 years, a significantly higher proportion in the USA have been screened for prostate cancer (p< 0.001). The risk factors for cancer differed in the two groups indicating a change in lifestyle accompanying migration. Utilization of methods for early detection of cancer was poor among the group in Sri Lanka despite the high incidence of cancer in the country.
A comparison of urinary β2 microglobulin levels in patients with chronic kidney disease of unknown aetiology and controls from Medawachchiya and Ja-ela
(The University of Peradeniya, 2013-07-04) Siriwardhana, E. A. R. I. E.; Perera, P. A. J.; Sivakanesan, R.; Abeysekera, D. T. D. J.
Chronic kidney disease of unknown aetiology (CKDu) has been reported in developing countries including Nicaragua, countries of Balkan region, Tunisia and Sri Lanka. Numerous studies carried out to date in these countries have failed to reveal the credible contributory factors for this disease. The objective of the present study was to compare the urinary β2 microglobulin (β2M) levels of CKDu subjects from Medawachchiya with those of normal subjects from Medawachchiya (Control M) and Ja-Ela (Control J). The test group consisted of 30 CKDu patients who were randomly selected from the CKDu patient register of Medawachchiya renal clinic. Normal age and sex matched individuals were selected as controls from the same division (Control M, n=30) and from Ja – Ela (Control J, n=30), an area which has been declared to be free from CKDu. Spot urine samples from all the subjects were collected and β2M estimated in duplicate using an ELISA test kit (BIOQUANT, B-2MG BQO10T, Germany). The mean urinary β2M level in CKDu patients (1.24 ± 0.71 μg/mL) was significantly higher (p<0.05) than that of control groups M (0.16 ± 0.05 μg/mL) and J (0.17 ± 0.05 μg/mL), while the control groups M and J had similar β2M levels. The urinary β2M levels between males and females of each of the three groups revealed no significant (p > 0.05) differences. Urinary β2M was significantly (p < 0.05) higher in males (1.31 ± 0.76 μg/mL) of the test group than of the males in the control groups (0.14 ± 0.04 μg/mL and 0.18 ± 0.05 μg/mL, respectively, in groups M and J). Similarly, significantly higher β2M concentration was seen in females of the test group (1.14 ± 0.65 μg/mL) than in females in the control groups (0.17 ± 0.05 μg/mL and 0.16 ± 0.05 μg/mL, respectively, in groups M and J). Renal tubular function based on urinary β2M showed a significant difference between those afflicted with CKDu and controls in the CKDu prevalent Medawachchiya Divisional Secretariat, as well as those from Ja-ela. Urinary β2M excretion is significantly higher in those affected with CKDu.
A computer based statistical tool to analyze the correlation among DNA sequences
(The University of Peradeniya, 2013-07-04) Jayarathna, P. G. S. S.; Sooriyapathirana, S. D. S. S.; Yapa, R. D.
DNA is the molecule of life. DNA sequence analysis is the key for understanding many biological questions. In bioinformatics, statistical techniques such as frequency distribution techniques, alignment algorithms, hypothesis testing, and clustering techniques are used to analyze the correlation among DNA sequences. Furthermore, comparing lengths, GC-content, AT/GC ratio, repetition of small sub-sequences and the analysis about restriction sites are the most basic analysis on the DNA sequences. Pie charts and the frequency tables can be used to analyze nucleotide distribution among DNA sequences. In DNA sequence analysis, sequence alignment is one of the most important steps to identify the similarity regions between DNA sequences, because it reflects functional, structural, or evolutionary relationships among them. Since the process of alignment algorithms like Smith-Waterman’s are very time consuming, the BLAST algorithm can be used as a time efficient procedure because it addresses the fundamental problems and the algorithm emphasizes speed over sensitivity. Cluster Analysis is also associated widely in DNA sequence analysis. The DNA analysis by using different statistical techniques requires several statistical tools and demands considerable expertise in statistics. Therefore, an attempt was made to design a user friendly computer based statistical tool to analyze one or more DNA sequences in different paths of statistics and make a sequence alignment efficiently. The DNA Sequence Analysis Tool (DSAT) was developed and implemented. by using vb.net programming language in Microsoft Visual Studio 8. MSChart and MSChartVisualStudioAddOn tools were used to display graphic outputs of the tool. An analysis can be conducted under five options named as Nucleotide Distribution Analysis, Basic Analysis (GC content, AT/GC ratio and repetitions), Multiple Analysis, Pair wise Analysis and Cluster Analysis. The DSAT contains a collection of several statistical techniques in one application and quick in aligning DNA sequences. This statistical tool can be used by biologists and students with limited statistical knowledge in quick time to get more detailed information about the correlation among DNA sequences.
A greedy agent to solve the minesweeper game
(The University of Peradeniya, 2013-07-04) Damunugalla, Salinda; Walgampaya, Chamila
Minesweeper is a one-person game which looks deceptively easy to play, but where average human performance is far from optimal. Playing the game requires logical, arithmetic and probabilistic reasoning based on spatial relationships on the board. At the beginning, the player is presented with a board containing NxM squares which are all blank. Hidden among the tiles are mines distributed uniformly at random on the board. The task of the player is to uncover all the tiles which do not contain a mine. At each turn the player can select one of three actions (moves): to mark a tile as a mine; to unmark a tile; and to uncover a tile. Game play continues until the player has uncovered each and every square that does not hide a mine, while successfully avoiding all of the mines. In our research, minesweeper game has been redesigned as a key board controlled shooting game. While it can be played by human users we have developed a software player, which we called a greedy agent, to play the minesweeper game. Greedy agent is a rule based agent that uses prior acquired knowledge to achieve specified tasks. The agent stores acquired knowledge in the form of sentences. New sentences are derived from prior sentences during the goal seeking process. At each move the greedy agent collects the following information: Flagged cell count around the current cell, Mines Count in current cell, and the Uncovered Cell Count around the current cell. According to the collected information the agent can make sentences such as “If mine count of current cell is equal to unvisited or flagged cell count of eight neighbors of current cell then all those unvisited cells contain mines.” During the exploration, if a mine is found and flagged, the agent will look for a safe cell to move. If a safe cell is not found then greedy approach is used to find a safer direction to move. The agent calculates the probability of having a mine in each neighboring cell. Once the cell with the least probability to have a mine is found the agent moves in that direction. In situations where two or more directions have the same probability value, the agent chooses the direction randomly. We have simulated the game with different mines counts and our results show that the agent performs better when the mines count is large.
A historical analysis of the political participation of buddhist monks during the Polonnaruwa period (from 11th to 13th century a.d)
(The University of Peradeniya, 2013-07-04) Chandrika, A. M. M.
Much of the research done in ancient Sri Lankan historiography paid attention to political and religious issues. However, currently there is growing enthusiasm to explore and to further research other areas that are of relevance to understanding this important period in Sri Lankan history. The existing scholarship mainly focuses on the link between the state and Buddhism and that between the monastic life style and the economic role of the monks. As these studies have ignored political participation and the influence of Buddhist monks as a group, the main intent of the present study is to explore that aspect through primary sources. It is generally accepted that Buddhist monks played a prominent role in Sri Lankan politics during the Anuradhapura period and such political involvement continued throughout the latter era with certain notable developments. The present study aims at paying special attention to this political development during the Polonnaruwa period. The politics of ancient Sri Lanka was greatly influenced by the involvement of Buddhist monks. However, their activities and responsibilities changed over time. In this respect they seem to have taken a practical approach to diverse issues that confronted them. Therefore, it is proposed to discuss the contribution of the monks by concentrating on the exact nature of the Bhikkhu community, the challenges they had to confront and their responses to such issues in order to gain a deeper understanding of the influence of the monks in the political sphere and their intervention in the dynamics of the contemporary political situation. It is important to underline the fact that political connections were extremely important in the formation of a powerful Sangha organization. The evidence from primary sources shows that the role of the Sangha community was extremely important in the field of politics in the Polonnaruwa period in Sri Lankan history.
A linear programming model to recongnize the arbitrage in the currency market
(The University of Peradeniya, 2013-07-04) Alupotha, A. G. K. N.; Perera, A. A. I.
In economics and finance, arbitrage is the practice of taking advantage of a price difference between two or more markets. It involves locking in a riskless profit by simultaneously entering into transactions in two or more markets. The price of one country's currency expressed in another country's currency is called the exchange rates. In other words, the rate at which one currency can be exchanged for another.Moreover, exchange rate has long been viewed in monetary literature as an important channel of monetary transmission.In our analysis, exchange rates on July 11, 2012 of the currency markets of the United States Dollar (USD), Euro (EUR), UK Pound (GBP) and Japanese Yen (JPY) have been considered which are being mostly used as dominators in world trade. It is not obvious, but USD-EUR-GBP- JPY-USD conversion actually makes per dollar converted and most of the time this scenario can occur regularly for different conversions in different currencies. In our work, we formulated a linear programming model to recognize this arbitrage opportunity and hence arbitrage-free or less transactions can be formed in the currency market. In this model, we make available in USD to purchase other currencies and pump through the system. If at the end of the day we get back more than , then an arbitrage exists. According to optimal value of the objective function, there is an arbitrage opportunity if all the transactions are made through the system on that day. Therefore, a number of unnecessary transactions have to be restricted by the governments to make an arbitrage-free or less environment in the currency market. Moreover, deterioration of currency values has been one of the severe reasons to occur arbitrage opportunities. Whereas, the efforts to maintain the most effective exchange rates have a significant impact on domestic inflation.Hence, improving gross domestic product (GDP) and regulating the transfer of foreign currency reserves are the best strategies to maintain an arbitrage-free or less environment as it curbs the deterioration of currency value.
A low cost PCR diagnostic assay for determining the sexes of papaya (Carica papaya L.) seedlings
(The University of Peradeniya, 2013-07-04) Alahakoon, A. M. A. Y.; Dayananda, A. G. M. L. K.; Yakandawala, D.; Sooriyapathirana, S. D. S. S.
Papaya is an important fruit crop. In Sri Lanka, nearly 8,000 hectares of land is under papaya cultivation and the annual fruit production is 32,000 metric tons and the annual export value of papaya is Rs. 83 million highlighting, its economic significance. The breeding system of papaya is triocious (papaya is a polygamous plant with three sex types) because individual plants can exist as male, female or hermaphrodite. The presence of unproductive trees in orchards greatly reduces the productivity as growers have to maintain all the plants until the reproductive stage to identify the sexes. Therefore, the detection of sexes at the early seedling stage is considered the best to avoid this problem. Molecular analysis of sex determination genes, and subsequent development of DNA markers to detect the sex genotype provide a valuable tool to detect the sexes at an early stage of development. DNA markers to discriminate sexes in papaya have been reported previously. These DNA markers can detect female plants separately from the hermaphrodite or male plants. However, these markers have to be validated to the Sri Lankan papaya populations before using them in routine screening for sexes. Moreover, genotyping with sex specific DNA markers for papaya has to be cheap and quick so that growers can use the technology without significantly increasing the cost of production and select preferred sexes at a very early stage and cull all the unwanted plants. The present study was conducted to validate a sex specific DNA marker for Sri Lankan papaya populations and to develop a rapid reliable and low cost sex genotyping facility for Sri Lankan papaya growers. DNA marker SCAR W11 was used for the molecular identification of sexes in papaya varieties grown in Sri Lanka. A total of 36 plants, in which, six plants from each of the commercially available varieties of papaya, Sinta, Red Lady and Rathna and three local Sri Lankan papaya types based on the fruit shape, Pyriform, Elongated and Round were grown in the Green House at the Department of Molecular Biology and Biotechnology, University of Peradeniya. Leaf samples were collected from seedlings for DNA extraction by using CTAB method and PCR was carried out for the DNA marker SCAR W11. The sexes of plants were determined by observing the flowers. The cost required to conduct genotyping was calculated based on the market prices in June, 2012. The minimum time period required to run the complete analysis was also tabulated. The DNA marker SCAR W11 generated a PCR band for male and hermaphrodite plants and no band for female plants whose sexes were confirmed by observing floral structures at the reproductive stage. The genotypes of 12 papaya seedlings can be predicted within six hours after receiving leaf samples from the growers. The approximate cost is Rs. 500/- per seedling, and the growers can know the sex of their future plants and adjust the female to pollenizer plant ratio without unnecessarily wasting resources on unproductive plants.
A model to predict performance of a hybrid car in known traffic conditions
(The University of Peradeniya, 2013-07-04) Premaratne, K. M. G. R. S.; Gunawardane, S. D. G. S. P.
In order to find out the fuel consumption of a vehicle for a known driving pattern, it is necessary to test it at the field which is costly. In this study, a computational model was developed to predict the fuel consumption of two hybrid vehicles when they are virtually travelled in Sri Lankan road conditions based on the known performance characteristics (series-parallel/ full hybrid) published by Argonne National Laboratory, USA. In this model, vehicle speeds were discretized and corresponding fuel rates at those intervals were predicted by considering the acceleration and the velocity. Finally, the hybrid vehicles were virtually travelled in different types of traffic conditions on a selected route and corresponding fuel consumptions were predicted. It was found that the fuel consumptions were very close to the real fuel consumptions of the vehicles tested for the same route. Therefore, if the performance characteristic of a vehicle is known, the fuel consumption for a given driving pattern can be accurately estimated using this model.
A preliminary study on heavy metal accumulation in selected aquaculture systems in Sri Lanka
(The University of Peradeniya, 2013-07-04) Malavipathirana, S.; Wimalasiri, K. M. S.; Priyantha, N.; Liyandeniya, A. B.; Mubarak, M. N. A.
Accumulation of four heavy metals (Cu, Cd, Zn and Pb) in aquaculture sediments was studied with respect to systematically developed novel aquaculture sites from Batticaloa, and the findings were compared with an existing well established site from Chilaw. The results indicate that heavy metals have the potential to accumulate in all selected sites. Buildup of Zn was significant in pond sediments compared to the other metals with the highest value of about 1200 ppb. This may be due to anthropogenic inputs of chemical substances such as minerals for shrimp growth. The gradual development in the accumulation of heavy metals with culture practices is evident by the increased levels of Cd at aquaculturefacilities with continuous operation. However, availability of heavy metals for shrimps and surrounding environment depends on the chemistry of the sediment (for example pH, aerobic or anaerobic conditions). Pond preparation by means of heavy machinery and, discharge of water at harvesting are known to disturb the physico-chemical status of sediments. Unless care is taken, this would pose a major risk to animals as well as surrounding environment. Moreover, it is assumed that heavy metals other than Cu, Cd, Zn and Pb synergistically act in the aquaculture systems and surrounding environment. This may be attributed to the reported impaired quality of the products with chemical substances from some aquaculture producing countries.
A preliminary study on root and root canal morphology and endodontically treated mandibular first molars
(The University of Peradeniya, 2013-07-04) Fonseka, M. C. N.; Jayasinghe, R. D.
Study of root and root canal anatomy has endodontic, as well as anthropological significance. The mandibular first molar is the first permanent tooth to erupt into the oral cavity and considered as an important tooth in establishing occlusion in the permanent dentition. As it is considered to be more prone to caries than other teeth in the dentition, good understanding of its morphology and anatomical variations is important in clinical dentistry. This study was carried out to determine the number of roots, root canals and configuration and variations of root and root canal morphology in permanent mandibular first molars. Working length radiographs of 97 consecutive patients comprising 49 males and 48 females receiving root canal treatment for mandibular first molars were assessed using a standard radiograph viewer with extraneous light blocked under x2.5 magnification. All radiographs were assessed by a single experienced investigator. Sociodemographic (race, age, gender and ethnicity) and tooth specific (number of roots, and root canal configurations) data were assessed and documented. The sample consisted of 85.6% Sinhalese, 10.3% Tamil and 4.1% Muslim patients. Of the radiographs, 56.7% and 43.3% represented left and right lower molars, respectively. The incidence of 3 rooted lower first molars was 15.5%. Among Sinhalese the incidence was 15.66% (13 of 83 patients) and in Tamils the incidence was 10% (1 of 10 patients) Females had a higher incidence of 3 rooted molars (24.5%) compared to males (6.25%). The canal configuration of the mesial root represented type IV configuration in 88.7% and type II configuration in 11.3% of the cases. The configuration of the distal root showed type I configuration in 51.5%, type II in 21.6%, type III in 1% and type IV in 9.3% of the cases. When two distal roots were present, the canal configuration was type I in both the roots. According to the preliminary survey the incidence of 3 rooted lower third molars is 15% which is higher than the incidences shown in similar studies. The incidence of canal configurations in mesial and distal roots is similar to those shown in other studies. The present study indicates the importance of having a better understanding about the variation of root and root canal morphology of the permanent mandibular first molar, especially regarding the high prevalence of three rooted molars, to minimize the possible endodontic and surgical complications.
A premliminary study on the arthropod predatory community in the cabbage ecosystem
(The university of Peradeniya, 2013-07-04) Priyadarshani, T. D. C.; Hemachandra, K. S.
Cabbage is an important vegetable crop in Sri Lanka. Among the production constraints, insect injuries on cabbage have been highlighted. Cabbage insects are mainly controlled by applying insecticides. However, insecticide spraying is associated with environmental and human health consequences. Therefore, the need for alternative pest control strategies has been highlighted. Among the alternatives, biological control using predators has been recognized. The objective of this study was to explore the predatory community in the cabbage ecosystem. The predatory community in the cabbage ecosystem was investigated at Dodangolla and Galagedara during June-August, 2012. Predatory insects and spiders associated with cabbage crops were sampled using sweep nets, hand picking and pitfall traps. Sweep net sampling and handpicking were done at weekly intervals for ten weeks. Pitfall trap sampling was carried out at three stages of crop growth, namely seedling, growing and head formation. Two pitfall samples were taken at each stage of growth. Sampled specimens were preserved in the dry or wet state. Collected carabids, coccinellids and spiders were identified through previously published identification keys. Predatory species communities, abundance of predators, dynamics of predatory fauna were examined and the data were analyzed by using the Chi-Square test, in Systat 13 SPSS software. Three Coccinellid beetle species, Coccinella octomaculata (Fabricius), Coccinella transversalis (Fabricius) and Coccinella sexmaculata (Fabricius) were found in Dodangolla and Galagedara cabbage fields. Carabid species, Cicindela punctulata (Olivier) and Bembidion quadrimaculatum (Linnaeus) were found in Galagedara while Harpalus pensylvanicus (De Geer) was found at Dodangolla. Three spider groups, wolf spiders (Lycosidae), sac spiders (Clubionidae) and crab spiders (Thomicidae) were found in both fields. The presence of the above coccinellid species in vegetable fields have been documented, but the records of carabids were scant. Abundance of predators (coccinellids, carabids and spiders) varied significantly with the stage of growth of the crop, seedling, growing and head formation, in both fields (Likelihood (LH) χ2 =49.4 df=2 P<0.001). A similar significant variation was found in Dodangolla (LH) χ2 =37.7 df=2 P<0.001) and Galagedara fields (LH χ2 =13.8 df=2 P<0.001). The total predator counts as collected by sweep netting and handpicking within the ten-week period did not show a significant variation with time and similarly did not show significant variation by the fields. Predator availability in the field at Dodangolla, which was a pesticide-free field, was higher (61%) than the conventionally managed field at Galagedara (39%). Overall, the results indicate the presence of predators in the cabbage ecosystem and their response to insecticide use in the crop.
A retrospective study in necropsy findings in dogs with renal disease
(The University of Peradeniya, 2013-07-04) Ariyarathna, H. M. H. S.; Karawita, A. C.; Jayaweera, W. R.; Gunawardena, G. S. P. de S.
Chronic renal failure (CRF), the end result of chronic renal disease, is usually irreversible and involves progressive loss of more than 70-80% of functional nephrons. We analysed necropsy findings of 23 chronic renal failure cases of dogs reported to the Division of Veterinary Pathology from 2009 to 2012 with the objective of determining the gross and histopathological lesions (renal and extra-renal) associated with CRF. The mean age (± standard deviation) of the affected dogs was 5.7 ± 1.2 years. Fifteen animals (65.2%) were males. Eight (34.7%) were crossbred while the rest comprised other breeds. Gross renal pathology included irregular cortical surfaces (100%), firm consistency of kidneys (100%), pale kidneys (78.2%) and reduced cortical width (34.7%). Histopathological examination of the 23 kidneys revealed moderate (57.14%) to severe (42.86%) interstitial fibrosis, compensatory tubular hypertrophy (61%), tubular atrophy (30%) and glomerular sclerosis (4.6%). An inflammatory cell infiltrate predominantly composed of lymphocytes was evident in 90.47% cases while the major cell types were neutrophils and macrophages in 8.69% cases. The kidney lesions were morphologically diagnosed as chronic generalised interstitial nephritis (n=19) and pyelonephritis (n=2). The extra-renal lesions observed were pulmonary oedema (100%), ulcerative haemorrhagic gastritis (60.8%), soft tissue mineralisation (39.1%), fibrinous pericarditis (26%) and fibrous osteodystrophy (4.3%). The most common conditions associated with CRF were chronic cystitis (13.8%), prostatitis (8.6%), suppurative cystitis (4.3%), pyometra (8.6%), transitional cell carcinoma (4.3%), and hydronephrosis (4.3%). Although this study could not identify the specific aetiological agents responsible for CRF, the spectrum of the lesions encountered suggest a multifactorial aetiology.
A retrospective study on dirofilariasis in five districts in Sri Lanka
(The University of Peradeniya, 2013-07-04) Iddawela, W. M. D. R.; Adicarum, D. R. S.; Ranaweera, R. L. A. R.
Dirofilaria repens is the most important cause of human dirofilariasis in Sri Lanka. It occurs commonly in adults except in Sri Lanka, where children younger than nine years are likely to be infected. The present study was carried out to describe the patient and parasitic factors associated with human dirofilariais in Sri Lanka. A retrospective descriptive study was conducted in 80 samples of worms, referred by surgeons in Badulla, Kandy, Kegalle, Monaragala and Polonnaruwa during the past five years. Data on age, sex and site of lesion were obtained from the details given in the referral letters. Morphological identification of the worm was based on the maximum width, length and the characteristic cuticle with sharp longitudinal cuticular ridges. Sex of the worm was determined by the width, length and distance between anterior end and genital opening. The age of the patients ranged from 8 months to 60 years. Of the study group, 69% were less than 40 years of age and 50.7% were males. Out of 80 patients, 34.5 %( 27) of the patients were less than 10 years of age. The youngest patient was 8 months. The majority (46%) of the patients were from the Kandy district. Nodules were reported in the abdominal wall (2), eye (35), face (4), foot (4), hand (3), leg (3) and scrotum (24). The largest proportion (65/80) were subcutaneous nodules. The adult worm was found in the upper part of the body in 85.6%, eye being the commonest site (41%). The scrotum was the commonest site in the lower part of the body (23.9%). Out of all adult worms, 80.8% were females while 11.5% were male worms. Only one nodule in the eye had both male and the female worms. The average lengths of the female and male worms were 12.1cm and 7.47cm, and average widths of female and male were 478.3 cm and 405.6 cm respectively. In conformity with these morphological characteristics, the filarial worms identified in these patients were Dirofilaria repens. The active age group (< 40 years) was the most affected. There was no difference in incidence between the two sexes. This pattern was seen in the studies done in the last decade of the 20ᵗʰ century. Sri Lanka is an endemic focus of human dirofilariasis due to D. repens. Therefore, dirofilariasis should be included in the differential diagnosis of patients presenting with subcutaneous nodules at any site of the body.
A statistical tool to characterize sub-population data of biological species
(The University of Peradeniya, 2013-07-04) Idamawatta, I. G. C. G.; Yapa, R. D.; Sooriyapathirana, S. D. S. S.
Patterns of morphological variations of biological species are different for their sub populations. The morphological characteristics of a particular species may change due to environmental and genetic effects. There are several statistical techniques to summarize, analyze and visualize both numerical and categorical data. In statistics, there are several multivariate methods to characterize these sub-population data, such as Cluster Analysis, Principal Component Analysis, Factor Analysis, model ANOVA (Analysis of Variance) etc. By these statistical analyses, similar groups, correlated characteristics, difference between sub populations etc can be identified. Further by using pie charts, bar charts, box plots, scatter plots, etc. data can be visualized and made out to several patterns and distributions of each variable. In many biological studies data have to be analyzed statistically. Though several statistical software are available to analyze the data, most of them are not open source and are complex for biologists. Further, statistical analysis may be difficult for most of the biological researchers and they may not be familiar with handling statistical functioning and computations. Therefore, availability of software or tool that is convenient to understand and handle statistical techniques is a necessity. Further, accessibility of several help files and some assistances would be more convenient to the users. The main goal of this research was to introduce such a statistical tool that could be used to characterize geographically or spatially separated sub-population data of biological species. In this study, MATLAB was used to implement the standalone statistical tool called Morphological Analysis, which is user friendly and has several user guidance and help files to understand the way of handling statistical methods. The graphical summaries can be viewed by two or three dimensional ways. The menu items and step by step guidance procedures help to obtain the desire output without typing any functions or programmes. Thus the user can perform statistical analyses without having much knowledge about statistics. Therefore, this is useful in data analyzing purposes for biology researchers.
A study of the dynamics of a settling colloid
(The University of Peradeniya, 2013-07-04) Welivita, J.A.; Witharana, S.
Settling in particle suspensions formulate an important academic and industrial problem. In oil and gas, mineral processing, and effluent treatment plants, settling is the most desired. But in a host of other applications, especially those involving tiny particles, the challenge is to prevent settling. In either case, the knowledge of settling dynamics is imperative. Due to the complex dynamics of settling colloids, which is governed by the particle and fluid properties and geometries, the accurate prediction of settling rates has become very challenging. Besides, there exists no universal theory to tackle these scenarios. The popular Stokes settling theory is prescribed only for single-particle unhindered colloidal systems. Therefore it does not seem to fit densely-populated industrial colloids. In an attempt to fill the gap in knowledge, we recently conducted a systematic study on settling of polydisperse Al₂O₃-water colloids. We employed a combination of conventional setting-bed experiments, scanning electron microscopy (SEM) and MATLAB image analysis to examine the applicability of Stokes settling theory to predict the settling rates. For materials, we used Al₂O₃ nanoparticles in the form of dry powder. The particles were spherical in shape and polydisperse in nature. By mixing them with distilled water followed by ultrasonic stirring, we obtained stable 0.5wt% Al₂O₃-water suspensions. Then we constructed a titration curve and discovered that the IEP (iso-electric point) occurred at pH=9.8. We prepared a series of samples at pH=7.8 and measured the settling bed height with time. At each instance where the bed height was taken, a droplet from the sample was extracted and saved for SEM imaging. A MATLAB code was developed simultaneously to measure the sizes and the count of particles on these images. Finally the particle sizes computed from Stokes equation and settling rates were compared with MATLAB measurements. In conclusion we show that the Stokes settling theory can fairly accurately predict the settling rates of the studied colloid.
A study of the kiriamma danaya (alms giving for seven mothers) ritual in the Kandy district
(The University of Peradeniya, 2013-07-04) Guruge, K. P. G. C. Kumari
This ritual has a long history and has been practiced widely among Sinhala communities all over the island. The Goddess Pattini is considered a protector of the Sinhalese and people expect her blessings for fertility, prosperity, healing children from illnesses apart from protecting them from epidemic diseases, such as small pox and chicken-pox (commonly known as Ammawarunge leda). Moreover, when a woman is pregnant, the blessing of this Goddess is secured for the protection of the mother and the embryo and also for a safe delivery. At all these occasions people make vows to the Goddess Pattini and promises the deity that they would give alms to seven mothers in her name. This is called a kiriamma danaya. Once their wishes have been granted people believe that it is necessary to fulfil the promised to the deity with all purity. Unlike other similar rituals, this ritual is performed and alms are prepared by lactating mothers or elderly women, who have given birth and nursed their children. The ritual includes women dressed in white arriving at the house bearing flowers to accept alms, evocations to the Goddess Patthini, boiling a pot of milk and the blessing of the household. All previous studies focused on the formation of this ritual. In this study the main focus is the attempt to distinguish between the past and the present practice of this ritual. This study examines how the kiriamma danaya is practiced at present. Research was conducted in the Thumpane Divisional Secretariat Division. Data was collected through interviews, individual studies and group discussions. While this was a common occurrence in the past, it is becoming rare due to many socio and economic reasons, such as financial difficulties, inability to find women knowledgeable in conducting the ritual, due to busy lifestyles of people, due to too much pollution (Kili) around one's abode and due to the lack of commitment in people. These circumstances have give rise to a new tendency, which is to perform the ritual at the temple of the Goddess Pattini located near the Temple of the Tooth, in Kandy. Accordingly, one only needs to reserve the day by bearing the expenses of the ritual which will take place in the temple premises of the deity and to participate in the ritual. With this new tendency some of the latent functions of the ritual have been lost.
A study on the extent of usage of the e-library, Faculty of Medicine, University of Peradeniya
(The University of Peradeniya, 2013-07-04) Perera, P. A. S. H.
With the revision of the undergraduate curriculum of the Faculty of Medicine, the E-Library was established adjacent to the Medical Library in 2005. It provides the facility only for the academic community (academic staff and undergraduates) of the Faculty of Medicine. The objectives of the study were to investigate the extent of usage of the E- library and to identify lapses in the existing services. A questionnaire was used to survey the study population consisting of 1171 undergraduates and the entire academic staff (58) of the Faculty of Medicine. The percentage of respondents in the category of undergraduates was 98 % and that of academic staff was 1.8%. The latter was excluded due to the inadequate response rate. 51% of undergraduates were neutral about the importance of the E-library as a resource centre. However, 52% of undergraduates used the E-library very often. 53% used the E-library whenever time permitted. The time of usage regarding week days and weekends depended on the seniority of the batch. 60% of undergraduates were neutral about their satisfaction of the E-library. Cited reasons for their reservations were slow and old computers and operating systems. 74% preferred the Windows operating system to Linux. 43% of undergraduates used the E-library for e-mails, 61% to surf the Internet and 45% to prepare project reports. Facilities in the E –library should be improved according to the findings above.
A study on the impact of the grade five scholarship examination on the self-concept of the students
(The University of Peradeniya, 2013-07-04) Balasooriya, R. M. J. W.; Bandarathilake, K. W. A. C.; Premarathne, Y. G.; Wanninayake, H. M.; Wanninayake, W. M. M. P. K.; Senevirathna, Walter
The objectives of this study were to identify the level of self-concept and gender differences of those who pass and fail the year five scholarship examination and to identify the perception of teachers and parents about these students’ talents and skills. A mixed research methodology was adopted in this study. A deliberate sampling method was used to select 110 (n=110) students from a National school (1AB) and a Junior school (Type 2) in the Nikaweratiya Educational Zone in the Kurunegala district. A similar sampling method was used to select ten teachers (N=10) and ten parents (N=10) from the same schools. The survey was conducted among the students to measure their self-concept dimensions by using a questionnaire that was developed through the Fleming Courtenay revision of the Janis Field scale - 2005. Apart from this, the parents and the teachers were interviewed. Data were analyzed using both qualitative and quantitative methods. Three null hypotheses were derived from the quantitative data and these hypotheses were tested using a chi-square test, t-test and Pearson’s correlation test. Qualitative data were analyzed using thematic analysis. According to the results the first null hypothesis namely, ‘there is no significant connection between the levels of self-concept of students and their achievement at the year five scholarship examination’ (the chi-square value counted was higher than the theoretical value (9.49<112.239)) was accepted. The other two null hypotheses namely, ‘there is no significant connection between the self-concept levels and the gender differences of the student sample’ (the chi-value countered was lower than the theoretical value (3.14>1.009)) and ‘there is no significant difference between the self-concept scores and the year five scholarship examination marks’ (the calculated t- value of two tailed test was higher than the theoretical value (5.095>1.980)) were rejected. According to the cross tabulation, those who obtained high marks at the year five scholarship examination, had a high level of self-concept scale values. Meanwhile, according to the Pearson’s correlation results, there was a slightly positive correlation (r=0.18) between the year five scholarship marks and the self-concept marks of the student sample. Moreover, the parents of the students who passed the year five scholarship examination and also those of the failed students shared the idea that their children were eager to resume their studies soon after the examination. The interviews with the teachers too revealed that soon after the examination the active participation and active learning nature of the both, students who had passed the examination and those who had failed had increased.

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