UoP Theses

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1931-1981 ඇතුළත ශ්‍රී ලංකවේ ප්‍රාථමික සහ ද්විතීය අධ්‍යාපනය කෙරෙහි දේශපාලන සංකල්පවේදය (political Ideology) බලපා ඇති ආකාරය පිළිබඳ ඓතිහාසික විමර්ශනයක්
(University of Peradeniya, Sri Lanka, 1983) Ratnayake, J.
1935 -55 අතර කාලයට අයත් කොළඹ කවීන්ගේ කාව්ය ව්‍යාපරය පිළිබඳ විචරාත්මක විමර්ශනයක්
(University of Peradeniya, Sri Lanka, 1988) Chandasiri, Rev. Moradana
1939-1965 කාලය තුල ශ්‍රී ලංකාවේ රාජ්‍ය අධ්‍යාපන ප්‍රතිපත්තිය සැකසීම සහ ප්‍රධාන ආගමික බලපෑම් කණ්ඩායම් වල ක්‍රියා කලාපය
(University Of Peradeniya, Sri Lanka, 1982) Arthanayake, W. K. A. M. Indrani Chithra
1H NMR stydy the role of alumina fillers in conductivity enhancement in the PEO based solid polymer electrolytes
(University of Peradeniya, 2004) Wijesiri, W. D. D.
Conductivity, DSC and NMR measurements have been performed on (neutral) nano-porous polymer electrolyte systems. It is observed that the conductivity enhances due to the presence of filler up to 15 wt % and then decreases. The NMR results are consistent with the idea that the conductivity enhancement is due to increase in chain mobility and ionic mobility of the solid polymer electrolyte made by increased amorphocity of the electrolyte with presence of fillers. DSC results also demonstrated that the amorphous phase is increased by adding fillers.
A Case study of selected locations regarding the reasons for school non-attendance and the implications for agricultural development in Sri Lanka
(University of Peradeniya, 1982) Ranmuthugala, Janaki Devi
This case study of selected locations regarding the reasons for school non-attendance and the implications for agricultural development in Sri Lanka, has been dealt with under three main headings: 1. The influence of farmer education level on the adoption of modern farming practices. 2. The influence of schooling on children's attitudes towards agriculture, measured by job preference, the studying of agriculture as a subject in school and knowledge of agriculture. 3. Reasons for school non-attendance. All tests were run in respect of schooling, location and sex separately. The findings and recommendations presented here are limited to this case study only and should not be considered as conclusive or general. Data, tests and analysis have revealed four significant relationships which led to the investigation into the reasons for school non-attendance. The relationships are: 1. A positive relation between correct adoption of modern farming practices and farmer education level. 2. A positive relation between dropping out of school and preference for agricultural occupations. 3. A positive relation between dropping out of school and the studying of agriculture in school. 4. A positive relation between schooling and knowledge of agriculture. The indications are that school non-attendance will have a negative effect on farmer education level, which in turn will have a negative effect on the future of agriculture in the country. Therefore an investigation into the reasons for school non-attendance is justified. In this study the statistical tool used to assess the statistical significance of the data was the chi square test. As regards recommendations the two broad objectives are: 1. To improve the status and quality of the school agriculture programme 2. To minimise dropping out of school in Sri Lanka, It is hoped that while attempting to achieve these objectives the long range objective of attempting to achieve agricultural development in Sri Lanka could be somewhat met. Fig. 1 MAP OF SRI LANKA SHOWING STUDY LOCATIONS
A Case study of strengths and weaknesses of advanced level science education in Sri Lanka
(University of Peradeniya, 2010) Saluwadana, S. M.
The last education reform was introduced by the Government of Sri Lanka, in 1995 to face the challenges of the 21 century. The implementation of the reform was started in 1997 through out the country. The present study focuses mainly on weaknesses and strengths of Advanced Level science education in Sri Lanka. The main target of A/L students ts to pass the examination. But most of them have not realized the value of school attendance, practical works and project work. This has resulted the degradation of A/L education in schools. Therefore it has been a major concern of the educationist to explore a way of improving science education in Sri Lanka. The objectives of this study are to identify problems faced by students, to find out suggestions from teachers, teacher instructors, additional directors (science), to discuss remedial steps to overcome shortcomings in current education system, to enhance the quality of science teachers, and to promote science education in Sri Lanka by introducing an effective method. For this study questionnaires were given to 1023 students in 32 1AB schools in North Central, Central, Sabaragamuwa and Western Provinces. In addition 52 teachers, 25 teacher instructors and 15 science directors. There is a significant difference among the four provinces selected in this study. Although a majority of the students in the Sabaragamuwa Province and the Western Province indicated that the main reason for attending school because of good teaching methods carried out in the schools. However, students of the North Central Province and the Central Province stated the main reason for attending school because of the compulsory eighty percent (80%) attendance requirement. This study shows that there is a significant difference among the four provinces with respect to the student attitude on assessment procedures. It reveals that 52% of North Central Province students, 64% Central Province students, 71% Sabaragamuwa Province students and 79% Western Province students agreed that the school based assessment(SBA) procedures were helpful in increasing the productivity of their learning process. The majority of the Western Province students (65%) indicated that project work enhanced their knowledge to meet future needs. In contrary, Sabaragamuwa Province (72%), Central Province (64%) and North Central Province (63%) students expressed negative attitudes towards project work. Findings of this study indicated that majority of the student population (61%) are actively engaged in extra — curricular activities and the rest are involved only with their studies. Even in the North Central Province about 99% students attended tuition classes. All the students in.the other provinces who are following G.C.E. (A/L) attended tuition classes. The majority of the Education Directors and A/L science teachers agreed that the concept of “Science School” may be an effective solution to overcome the above difficulties and suggested to start one model school in each province.
A Case study on feasibility of school projects of the G.C.E. advanced level (science stream) curriculum: views of teacher community
(University of Peradeniya, 2009) Vathanie, M. S.
In our former education system, less priority was given to the activity based learning and teaching and hence secondary school leavers faced difficulties in fitting into the world of work. To overcome the above problem, School Project was introduced to G.C.E. Advanced Level students under the National Education Reforms of 1997. This study investigated the views of teachers and the extent to which project work has helped the students to develop a well balanced and integrated personality. The study also aimed to find out the constraints faced by teachers when guiding the students in their project work. The research sample comprised of 500 Advanced Level Science Stream teachers from popular and less popular 1AB schools in urban, semi urban and tural areas in the Central Province. A questionnaire survey and the direct interviews were the techniques used for data collection. Most of the questionnaires were administrated personally and some were mailed. Twenty-five Educational Authorities, Parents, Past Pupils and Students were interviewed with their consent, for further clarifications and to assure the conformity of the data. Analysis of data collected through questionnaire and the direct interviews revealed that only about 37% of teachers have obtained training in the A/L project work, while 61% have not obtained any training. But 79% of the teachers have experience in guiding students and about 90% of the teachers like to guide students in their project work. 67% of teachers like to guide science related projects, but 55% of the students like to do general projects. 72% of teachers stated that students were keen to follow instructions given by them. 42% of the teachers were of the opinion that students have enough time to do the project work while 40% of them stated that students do not have enough time to do both the projects. In teachers view, there is no correlation between project work and final examination results but there is a correlation between project work and economical status of students. It is realized that there is no correlation among teachers whose media of instructions are in all three languages namely Sinhala, Tamil and English and willingness for project work. According to the students view they face difficulties when selecting a project title, writing project proposal and project report due to lack of guidance by teachers. They expect more help from teachers. Most of the science stream past pupils were in favour of the project work as it had developed their skills and had been useful in their higher studies and career. Many parents disagreed with the project work, while educational authorities accepted that there was not enough monitoring for project work in schools. Further more, they were of the opinion that much weight should be given for project work through policy changes. On the basis of the above results, following conclusions and recommendations were made. Most of the teachers did not obtain any training relevant to the A/L research projects of students and the teachers lacked knowledge on guiding the project work. It is suggested that quite regularly or every year teachers should be trained on the project work and should eventually update their knowledge with time. Most of the students neglect the project work and it was a problem for teachers. It is suggested that a considerable weight should be given to project work through policy level changes. There seem to be less monitoring by the officials regarding project work. Therefore it is suggested that project monitoring in school should be done by the zonal officials in a scheduled and a planned manner.
A Case study on learning physics through problem based learning approach
(University of Peradeniya, 2009) Gunawardhane, V. D. K.
It is apparent that there should be a right background for the students to learn a subject like physics with full of concepts and that it cannot be learnt in isolation without the right environment. In promoting conceptual understanding of the students, certain areas might be important than the others which might affect in making them aware of their pre-conceptions and also making them believe the newly learnt correct concepts and further in the application of the new concept to everyday situations where they were failed to do so with the earlier concepts. There were several educational reforms to improve science education in Sri Lanka mainly trying to change the role of teachers as leaders and to change the role of students as passive learners along with the concept of learning to learn. In 1997 educational reforms for junior secondary and senior secondary were introduced to improve the student centered learning, transforming the teacher authoritative classroom into a place where more participation of the students is encouraged. However,still most teachers tend to use teacher centered method to explain concepts in science. If the teachers could guide the students to engage in appropriate learning activities and hands- on experiments it would greatly improve learning Hence this investigation was conducted to identify such problematic areas and to design an improved methodology to uplift the degree of understanding the concepts included in the subject physics, considering eight different schools in a non- industrialized city where most of the students are not highly motivated and not readily exposed to the subject matter, as the sources of data for the research. Advanced Level students who study physics of eight government schools and the teachers, principals of those schools and also some of the directors involve in the subject in this particular area were provided with appropriate questionnaires . Besides, verbal comments of some unstructured interviews with the confronted population were also gathered. The evaluation of the information gained showed disparity of the levels of the exposure to the subject by the students between the schools. For the second stage, to clarify the above idea and to see the effect of two different teaching methodology on students’ performances a detailed study was carried out selecting two schools out of the original lot. To build up two groups of the students and to see the prior knowledge of the students, a pre-test was administered for all the students in four twelfth grade classes of physics in the two selected schools, school A and the school B. Further mean marks for the pre-test showed that the students in both schools were equal level and therefore the school A with two classes was selected for the study. According to the pre-test marks of the individuals, two equal groups were made and they were taught the selected topic, in two different teaching methods, Problem Based Learning (PBL) and the Teacher Centered Learning( TCL). The topic Newton’s laws of motion in the section mechanics in the Advanced Level syllabus was chosen because there are new scientific concepts to be understood by the students. TCL and PBL were practiced by two different teachers. TCL students were taught the concepts in the topic laws of motion in a more conventional way with non- sophisticated and inexpensive teaching aids while the PBL students used an active co- operative learning environment. Assessments were accomplished during the period of the study both for PBL and TCL groups. The pre-test was repeated at the end of the period of study for the two groups. To obtain a more precise quantitative measurement a post test was also carried out to all the students in both PBL and the TCL groups. The results revealed that this proposed methodology blended with specific ill- structured problems and with specific activities was more advantageous than the presently practiced conventional methodology because of more opportunities for the students to participate actively in the classroom. Further the proposed new methodology was also successful in uplifting the degree of understanding the scientific concepts than the other method and this difference was attributed to the emphasis of the items in the two sample t-test (Table No.4.E.1). This investigation has further shown that the students’ performances through better understanding of the concepts can be uplifted by developing new methods attractive to the student. Hence it should be the teachers’ responsibility to launch an appropriate methodology for the section to be taught by having a proper understanding of the students’ prior knowledge, mental capacity, ability of grasping subject matter etc. The introduction of PBL into the classroom situation resulted significant changes to the way in which the teaching and learning were viewed before, that the PBL environment promoted deep learning rather than surface learning which is highly seen in the conventional programmes. As students were required to engage in group work enormous time was allocated for them to discuss, clarify and elaborate the concepts they were supposed to learn by producing a group of students really confident in mastering the concepts to any situation at the end. Promoting conceptual understanding of the students especially in an unfavorable background and of a subject like physics is a big challenge! This challenge will enhance the interest in the process of teaching as well.
A Case study on school projects of the G. C. E. (A/L) curriculum (science stream): views and constraints of students
(University of Peradeniya, 2009) Shiyana, M. Z. S.
The school education of Sri Lanka is highly examination centered and students have to engage in formal curriculum with traditional teacher centered learning and teaching. There have been number of defects caused due to this type of learning by students. Lack of skills and personality development produced the citizen with low focus to the world of work. Introducing school projects to the GCE (A/L) curriculum is expected to create a path to produce students who would fit to the application world. Students usually involve in these projects as it is compulsory for the final examination. Therefore it is important to investigate whether the introduction of projects moves towards its goals. 1AB schools of the Central Province were selected for this study. Information was gathered from all Grade 12 and 13 science stream students and past pupils of all three medium. (i.e. Sinhala, Tamil, English). The questionnaire designed was the major instrument used for data collection. Separate questionnaires were prepared for school students and past pupils. Formal and informal interviews were conducted to get in depth information and fill the gaps. Data were analyzed percentage wise, statistically and also by incorporating the evidences at the interviews. Although there were plenty of opportunities to develop a well balanced and integrated personality from the projects, 98% of students felt that it consumes their time of studying. | Despite the fact that a majority of students did not show any interest towards the projects, a more than 50% liked to do projects. There were no relationships between projects and the fields of interest. 80% past pupils said they did not get a considerable use of projects for their career.75% of students believed that it was a stress instead of relaxing the mind. Educational authorities strongly felt the topic selection was the reason for the failure of projects. Parents strongly believe that the projects grasp the working time of their children. Most of the students do the projects since it is compulsory to sit for GCE A/L examination. The way of conducting the projects is the major factor for the failure of successful completion of the projects. All the education officers accept the fact that the school projects have not reached the intended goals.
A Case study on the conceptual understanding of electricity and electrostatics concepts of grade eleven tamil medium students
(University of Peradeniya, 2015) Raveendran, A.
The main objective of teaching science in the school curriculum is to enable the students to comprehend basic concepts of science in order to empower them to resolve the problems they encounter in their daily life successfully. Practical experiences by teachers of science, the real classroom situations clearly indicate that in reaching the above objective, accuracy and clarity in Conceptual understanding by the learner is a must. The purpose of this research is to investigate the ·level of Conceptual understanding of Physics by the students studying science in Grade 11 classes of selected four schools in the Kandy district. This study further attempts to address the issue of Conceptual understanding of scientific concepts in actual Sri Lankan classroom situations through the Methodology of Conceptual Development. Under this methodology the learner follows a route of three learning stages, namely, Exploration, Concept Development and Application. By the application of modern educational classroom techniques such as Physics Educational Technology(PHET), Simulation Technology, Video Clips and group and pair work, this study has attempted to give the learner a realistic experience in the application of Physics concepts learnt in the classroom. Instead of using traditional educational resources this study has used the technique of PHET simulation, which is interactive, dynamic and constructive, by employing real equipments, reading resources, or chalk-Talk lectures appropriately. The results of the research prove the fact that , when compared with the traditional Chalk and Talk methodology of teaching which is still widely practiced in man y schools in Sri Lanka, which failed to bring about desired results, the Conceptual Development Method works well in any classroom situation to the satisfaction of not only the students and teachers but also the other interested parties as well.
A Case study: vegetation study at the Meethirigala forest reserve
(University of Peradeniya, 2009) Prematilleke, K. P.
A study was undertaken to gather baseline information on structure and composition of the vegetation in the Meethirigala Forest Reserve, one of the fragmented forest patches located in the wet zone of Sri Lanka. This reserve is surrounded by an urbanized area and as a result it is frequently disturbed by human activities. For the study, I have identified four sites as highly disturbed, disturbed, less disturbed and undisturbed area. Vegetation was investigated by plot sampling using quadrates. Twelve, 20 m x 20m quadrates and thirty six sub plots, (each 5 m x 5m) were enumerated, All trees with a diameter at breast height (dbh) larger than 10 cm or greater than >1 m in height were recorded and identified. Density and Shannon Diversity Index were calculated accordingly. The vegetative structure and composition varied between the sites. According to the results the site located within the monastery (undisturbed area) has a significantly different vegetative stucture and composition compared to the sites at boundary (highly disturbed), near the public road (disturbed) and site located close to the stream(less disturbed). Endemicity and diversity are also higher than the other three sites hence suppose to be an undisturbed area. Stratification showed a very similar pattern to a dipterocarp forest type. Identified forest species in study sites gave a total of 164 plant species belonging to 44 tree species, 33 genera and 27 families in the greater than 10 cm dbh woody species. Of this total 164 species, 38 (23%) species are endemic to Sri Lanka. Further, 41 (25%) timber species, 16 (10%) fuel wood species, 33 (22%) medicinal species and seven (4%) invasive species were recorded. The distribution of Ochlandra stridula was observed over the other plant associations. Influenceof O. stridula on other plant communities were identified as a threat to the biodiversity and should be prioritized for further research on it, for conservation of forest species and monitoring of biodiversity in forest reserve.
A Classification method for optical phenomena of cat's - eyes and stars in minerals
(University of Peradeniya, 2011) Kumaratilake, W. L. D. R. A.
In gemstones, needle-like inclusions originate by crystallization of exsolved impurities which occupy structurally favourable specific crystallographic directions in the host mineral during cooling. Countless sub-microscopic needle inclusions near the surface of a cabochon-cut gemstone scatters and reflects light and forms an image that can be described as an optical-loop called a Cat’s-eye. Two or more optical-loops cross each other and form a star effect or a network of stars in gemstones. Cat's-eyes and formation of stars and star networks are phenomena that are least explored areas in gemmology. Objective of this study is to develop a classification method of cat’s-eye and star phenomena applicable to all gem minerals, revealing the effects in profound detail. The study introduces quantitative and qualitative classifications to aid systematic study of cat's-eyes and stars. The quantitative approach (a) reduced the gamut of least explored cat's-eyes and stars into mere eighty nine types, a stereogram and a code visually illustrating complex star-networks analytically and the stereogram enabling the decoding of codes, (b) surfaced many missing links of cat's-eyes and stars laying a platform for new discoveries like sinhalite cat’s-eye. The qualitative comparison scale portrays the quality of a cat’s-eye/star from a commercial standpoint and determines the subjective value addition of the stone. Both quantitative and qualitative research methodology was utilised to devise the classifications. Hypothesis test was carried out from observational study of needle inclusions including those given in previous literature. The result is significant that needles orient parallel to each other and parallel to symmetry-axes-of-rotation of the host crystal and form the optical-loops perpendicular to those even in rough gemstones. In a fashioned cabochon (sphere) an optical-loop moulds into a circular loop-plane, and | hovers above the surface of the stone at a specific distance. This hovering-distance (d) is determined by the Wuthrich’s equation d = 1/2(n-1) mm which relates to the radius of the sphere (r) and the host refractive index (n). Several symmetry-axes-of-rotation produce angled loop-planes which crisscross to form a star-network. To better understand the effect, the study utilized the relation of cat’s-eye and star phenomena to the host crystal symmetry. The quantitative model developed here used this relation and incorporated the loop-plane as an extra symmetry element in the host stereogram. Model’s parameter is the formation of loop-planes perpendicular to symmetry-axes-of- rotation and the variable is the component symmetry-axes-of-rotation, one hundred and six in total within the ¢hirty two symmetry classes. The symmetry-axes-of-rotation are categorized into stand-alones (e.g. Ag), sets (e.g. 6A), and combinations (e.g. A42Az, 6A24A33A4). The stand-alones produce twenty seven cat’s-eyes, and both the sets and combinations yield sixty two star-networks, which is an exhaustive number for entire range of minerals. The total of eighty nine cat’s-eye and star effects has been uniquely identified and a code has been developed to document and classify each one of those on the basis of component symmetry-axes-of-rotation producing the effect. Thus, a four- level and four/eight/twelve-digit code has been proposed in the classification. Many gemstone examples were fitted into the coded classification and this included speculations. However, Sri Lankan star sapphire showed some inconsistency and additional data had to be gathered to improve it. Certain twin crystals display symmetries which deviate from their simple crystals and the new classification scheme is consistent with:such compound crystals too. New scheme was also applied to star sapphires showing polyasterism to uncover the details of displaced sections of those crystals produced by deformation. The classification was finally applied on man-made fibre-optic cat’s-eye material (amorphous) to learn the commercial manufacture of the star stones. A qualitative-model was developed to compare qualities of cat’s-eye/star phenomena. The parameter is the hovering distance d of the phenomena whilst keeping constant the radius (r) of the stones under comparison. Subjective variables were the three quality factors of the comparing phenomena - intensity, definition and colour. To represent qualities of entire range of known phenomena a sample of twenty eight cat’s- eye/star species were selected with radius r = 5mm. The quality factors of seven commercially accepted species were benchmarked and the benchmarks were utilized to develop a comparison scale. Comparison scale demonstrates relative position of a given cat's eye/star with respect to a benchmark.
A Classification technique for face recognition based on locally merged Codebooks
(University of Peradeniya, 2014) Thileeban, V.
Automatic recognition of people is a challenging problem which has received much attention during recent years due to its many applications in different fields such as, law enforcement, security applications or video indexing. Face recognition is a very' challenging problem and up to date, there is no technique that provides -a robust solution to all situations and different applications that face recognition may encounter. Face is the most common biometric used by humans. Face recognition is to recognise a person from a given two dimensional image . Face recognition technology solves this problem since a face is undeniably connected to its owner except in the case of identical twins. Difficulties of face recognition are inter-class similarity and intra-class variability due to head pose , illumination conditions, expressions, facial accessories and aging effects. In face recognition the system compares the given individual with who they say they are and gives a yes or no decision after that the system compares the given individual to all the other individuals in the database. In this work a framework is proposed to classify faces using scale-invariant feature transform (SIFT) and speeded up robust features (SURF) through a novel method which is compared with the bag-of-feature approach. The images of AT&T and Yale faces are classified through the system that involves identification of regions of interest and representation of those regions SIFT or SURF descriptors, construction of codebooks which provides a way to map the descriptors into a fixed-length vector in histogram space , and the multi-class classification of the feature histogram is performed using nearest neighbor method in the case of bag-of- feature approach. In our proposed frame work the extracted descriptors of an image is voted against the locally merged codebooks to predict the subject, without the need for mapping the descriptors into a fixed -length feature vector and then feeding it to a classifier. The AT&T face database contains 400 images for 40 persons with ten images per person. The Yale face database contains 165 images for 15 persons with 11 images per person. The testing results show 70% classification accuracy in the AT&T faces whereas 80.1 % in Yale faces ' using SIFT. When using the SURF descriptors, the results show 77% classification accuracy in the AT&T faces whereas 78.9% in Yale faces. Our proposed technique achieved 91% classification rate using SIFT descriptors and 92% using SURF descriptors in AT&T faces . The proposed method not only shows better accuracy in classifying faces of different subjects but also drastically reduces the computational time and storage as that of bag-of-features approach.
A Colour picture guide on fish and fishing gear required For G. C. E. (Advanced Level) biology students
(University of Peradeniya, 2003) Dhanasekara, D. P.
This study was intended to produce a colour picture guide on fish and fishing gear for General certificate of education (Advanced level) Biology syllabus. Aquaculture is a sub unit of Applied Biology unit. Facilities in the schools are insufficient to do the lessons effectively. According to the limited period of time it is very difficult to devoted more time to this sub unit. There is no picture guide under this section. After analyzing the questionnaire which was distributed among the randomly selected Biology teachers in Kandy district, the needness of a colour picture guide was known, Selecting aquatic species were done according to the fishing gears in the syllabus. Such as gillnet, Long line, Pole and line, Scoop net, Trawl net and purse seine are the fishing gears. According to the demersal fishing and pelagic fishing, aquatic species were sub divided. After separating large and small species of demersal and pelagic fishes, biological classification has done. In brackish water most common fish species were selected as edible and ornamental fish. Inland freshwater endemic and endangered fishes were included. This picture guide will assist not only aquaculture sub unit, but also unit-2 Bio diversity and unit -8, man and the environment of Advance level biology syllabus.
A Comarative phylogenic analysis of selected species of exacum of Sri Lanka with Osbeckia Octandra
(University of Peradeniya, 2013) Maheswaran, S.
The Exacums are members of the family Gentianaceae. These annual species are grown as flowering pot plants in the Western hemisphere for its beautiful and profuse blue or white flowers . There are eight Exacum species found wild in Sri Lanka: Exacum axillare, Exacum macranthum , Exacum pallidum, Exacum trinervium, Exacum walkerii, Exacum pedunculatum, Exacum petiolare and Exacum sessile of which four .are designated as threatened species. This study was conducted to determine the phylogenetic relationships of four of the endemic Sri Lankan Exacum species, E. trinervium; E. macranthum, E. walkerii and E. pedunculatum which show the potential for application in the floricultural industry with the non-endemic, commercial species E. affine, to compare their sequences of the Internal Transcribed Spacer (ITS) region of l8S-26S rDNA for use as a possible DNA typing target and to compare the Exacums of Sri Lanka with the morphologically similar species Osbeckia octandra. DNA was isolated from younger leaves of the plants ; the ITS region was amplified by Polymerase Chain Reaction (PCR), and the nucleotide sequences of the PCR products were determined. The amplified products of the ITS region of different species were estimated to be 554-720 bp. Multiple sequence alignment of the ITS sequences were carried out using ClustalW program and phylogenetic relationship of the species was determined by using Mega 4.0.2 package . The two endemic species E. macranthum and E. trinervium clustered together in the phylogenetic tree while E. walkerii and E. pedunculatum formed a separate cluster ..The exotic species E. affine diverged from the cluster and branched separately. Osbeckia octandra did separate from all Exacum species.
A Comparative study of amylase activity of germinating seeds of Mung Bean (Vigna Radiata L.) Cowpea (Vigna Unguiculata L.) and Soya Bean (Glycine Max L.)
(University of Peradeniya, 1999) Bokalamulla, A. A. K.
The total and α-amylase activity of germinating seeds of three pulses, mung bean, cow pea and soya bean, were determined and compared by a spectrophotometric procedure using iodine as the colour indicator. The objective of the study was to develop suitable source of amylase for the starch-amylase assay, included in the G.C.E. (Advanced Level) Biology syllabus. The study showed that the three species displayed amylase activity at all.stages of germination, starting from 24h after soaking. The total amylase activity in all extracts was higher than α-amylase activity alone thus indicating that other amylases were also present in the germinating seeds. The soya bean seeds soaked for 24 h. showed amylase activity but this was not found to be due to any α-amylase activity. In a previous study the mature seeds of soya bean have been shown to contain very active β-amylase activity. This study also showed that the germinating seeds of mung bean displayed comparatively higher α-amylase activity than the other two pulses used. Mung bean seeds showed a low level of α-amylase activity initially but increased significantly during the following 48-72 h period of germination. Mung bean seeds also showed the highest germination rate among the three pulses investigated, thus showing a positive correlation between the onset of germination followed by radicle extension and α-amylase activity. On the other hand, in cowpea seeds the amylase activity remained steady during germination, and the germination rate was rather slow. The presence of high α-amylase activity in germinating seeds is beneficial for a starch-amylase assay because α-amylase reduces the colour intensity of iodine rapidly with reaction time.The results showed that mung bean seeds germinate for 48 - 72 h after soaking have the highest α-amylase activity among the three species studied. Therefore mung bean seeds could be used as a suitable source of α-amylase activity for laboratory assay. In addition it was found that 0.1 M acetate buffer for the extraction of enzyme and in the reaction medium could improve the reliability of the assay.
A Comparative Study of Catullus 64 and Vergil'sOrpheus-Eurydice Episode in the Georgics and His Aeneas-Dido Episode in the Aeneid
(University of Peradeniya, Sri Lanka, 1984) Moldrich, Shona
A Comparative Study of the Concept of Sin and Evil in Buddhism and Christianity
(University of Peradeniya, Sri Lanka, 1998) Sumangala, Rev. Thalampitiye
A Comparative study of the knowledge on biodiversity in town schools and village schools in Kandy
(University of Peradeniya, 2004) Manoharan, S.
Biodiversity is a unit in the G.C.E O/L Science syllabus. Teaching experience suggests that there is a knowledge gap in Biodiversity between town school students and village school students. The village school students have a better understanding in identifying plants, their importance and medicinal aspects compared to the town school students. Hence, the theoretical knowledge of town school students is much ’ better and advanced than of village school students. To identify these knowledge gaps a research study was conducted. Data was collected by a diagnostic test, interviews and discussions with Grade XI Science students and. teachers from selected schools located in the Kandy town and nearby village areas. Information gathered from other sources such as Grade XI Science syllabus and Teacher’s guide was also used to strengthen the research study. The research study identifies the problems faced by the town school students and village school] students in the subject of Biodiversity. The major constraint in town school was the lack of practical knowledge, where as the limitation in village school was the lack of infrastructure facilities including appropriate teaching staff. The study suggests different teaching methods and activities that a teacher could introduce to improve the situation. It is important to create an interest in Biodiversity in town school students as well as village school students.
A Comparative Study of Theravada and Sarbastivada Canonical Abhidhamma
(University of Peradeniya, Sri Lanka, 2009) Peng, Ven. Chan Fook