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Early history of education in Ceylon (from earliest tiomes up to Mahasena)
(University of Ceylon, 1966-11) Jayasekera, M.A.
The traditional history of Ceylon is considered to have started with the advent of Gijevs to Ceylon. The story of education, or that of the activities of Vijaya and his immediate successors during this period is hardly available. A subsequent event, namely the introduction of Buddhism however changed this situation. With the arrival of Mahinda and his sister Sanghamitta in Ceylon, and the consequent spread of Buddhism in the country, a new religion and a new culture took firm root in the Island. Arts and crafts, architecture, education, literature, may all be considered to have sprung from this one single event. Thus the story of education in early Ceylon is in a way the story of the spread of Buddhism in the country. However, this study has been confined mainly to examining the educational aspects of the activities of our early ancestors. This study may broadly be considered to contain two distinctive sections, the background and the story proper. Chapters one to six are devoted to examining the background, while the rest, chapters seven to eleven, are devoted to examining the effect of such a background. On the whole it may be said that this study has focussed attention on the fact that education has emanated from the religious teacher, starting with Mahinda himself. Even the secular form of education that may have prevailed in earliest ‘times has also been traced to the viharas and aramas, the residences of the early theras, although we have isolated instances of teachers like Pandula who may be considered to have functioned irrespective of any religious bearing. Panqula however, lived before the advent of Buddhism into the country. In this survey it has been observed that the practice of keeping ‘historical records', and the custom of maintaining the system of bhagakas kept alive the tradition of literary activity and study in the country. The building of religious edifices, and secular buildings, like thtpas and palaces etc., and the incising of inscriptions etc. on hard granite and the like kept alive the art of the craftsman and the artist.
ලිඛිත සිංහලය : විග්‍රහාත්මක විමර්ශනයක්
(University of Peradeniya, 1969) De Seram, D. D.
Abstract is attached
The political history of the Kingdoms of Yapahuwa, Kurunegala and Gampala
(University of Peradeniya, 1970) Gunasinghe, Pattiyage Ananda Tissa
The subject covered by this Thesis is the political history of Sri Lanka during the period after the death of Parak- -ramabahu II of Dambadeniya, and the rise of Parakramabahu VI of Kotte in the first decade of the fifteenth century. This period saw fundamental changes in the nature and structure of the State in Sri Lanka, The kings of Anuradhapura and Polonnaruva claimed and exercised suzerainty over the whole country, ruling the various areas through governors and other officials appointed by them. The large surpluses of food that resulted from a regular cultivation of rice in a tank-based agri- -cultural system enabled the rulers of these kingdoms to maintain a powerful army and a well organised administration. While there were revolts against various kings and dynasties, these were attempts to supplant the rulers rather than attempts to destroy the unitary structure of the State in order to establish provincial centres of power. The one systematic attempt to establish regional autonomy, i.e. the revolt of Rohana during the reign of Parakramabahu I, was ruthlessly crushed by the central government. The political structure of the country during the period covered by this study is a complete contrast to this. After the death of Parakramab&ahu I of Polonnaruva, there was,except for a brief period under Nissankamalla, virtual anarchy in the country until the commencement of the reign of Vijayabahu III, who established himself at Daibadeniya. He, his son Paraékramabahu II, and the two sons of the latter, Vijayabahu IV and Bhuvenekabahu I, brought the larger portion of the Island under their control, and for a period of nearly fifty years the country enjoyed a degree of stability. But with the death of Bhuvenekabahu I in 1284 A.D. as a result of an invasion launched by the Pandyan kingdom, and the destruction of the kingdom of Yapahuva, the disintegration of the State commenced, When the Dambadeniya dynasty reestablished itself again, in 1296 A.D.e, its rulers could set up their capital only at Kurunagala, with the result that they lost control of the northern portion of the kingdom. After the death of Pardkramabahu IV of the Dambadeniya dynasty, the country gradually broke up into a large nwaber of kingdoms and principalities, until, in 1350 A.D., the effective rule of the consecrated king of the Island was confined only to a small area in and around Gampala. Another feature of this period was the establishnent of a separate centre of political power in the Jaffna peninsula, which, in time, became linguistically different from the rest of the Island. At the end of the period of our study there emerges a picture, not of one unified, integrated State covering the whole Island, governed by a universally accepted ruler, but a situation where the consecrated ruler of the Island exercised authority only over the central and south-western portions of the country, (though he claimed nominal authority over the whole Island), depending for his government on the support of powerful noble families, with a weak control over the various regional authorities. This change in the structure of the State was accompanied by a change in the base of the power of the State from the dry zone section of the Island $6 the wet zone section, and an analysis of this change suggests that the transformation in the nature of the State occurred precisely because of this chanve of economic environment. In contrast to the dry zone, the quantum of land available for distribution was much less, and even the land distributed, and the land retained and cultivated by the State, yielded a lesser surplus over and above subsistence needs. As a result, the revenues of the State fell, with the State no longer being able to maintain the powerful military forces that were its ultimate saurce of authority, and its ultimate sanéthon against revolt and separatism by its regional authorities. Along with these developments within the Island arose a situation in the outside world where a great upsurge of trade was taking place. The Crusades, in West Asia, led to a great demand for eastern goods, including products of Sri Lanka such as spices and other goods, to be sold in Europe, and this was accompanied by technical developments in Chinese nautical science, which enabled Chinese mariners to sail directly into the Indian Ocean for purposes of trade. South India, Sri Lanka and other south-east Asian countries formed part of a trade net-work operated by South Indian guilds. With this expansion of trade, the demand for agricultural and other products found in the south-western and central regions of Sri Lanka increased, with the result that the hereditary land-owning class, which formed the official hierarchy of the State, greatly increased its economic wealth. This in turn resulted in the rise of powerful noble families, such as the Menavaras, the Ganavasis, the Alagakkonaras, etc. who, on the one hand, set up regional centres of autonomy, and on the other hand, exercised considerable power and influence in the central government. It is this interaction of forces that forms the subject matter of this study.
Studies of the immunological response of puppies, monkeys and children to toxocara canis (Werner, 1782)i nfectiion
(University of Peradeniya, 1971-01) Vasudevan, Bundla
The course of the naturally sequired grenatal infec- tion of 7, canis in pupples from their birth to 4 menthe of age wae followed, The feecal Joxpcgrg egg count trends, the antibody response and the Toxoqgrg worm burden2xapinalin at pon-mrmnieiw on death or after being killed at lflfi daye of age in these puppics heve been reperted v l!:mumn: 1), . - -was of the effects of n}cunroeuen en pupriee - aged 4 to 6 weeks and naturelly infected with Joxocgrs Y '§ ‘wae made ('«‘xpoflmnt 2 end 3). ¢ R The pattern of oimhmry anti-Toxpegrg sntibodies i *n been studied in theee pnppxu aperinfected with diffe- v Pent doses and in those which received rcingle and multiple fl"' of T,csnig infective ova by megns of conglutinating complement absorption test and Cuchterlony ager diffusion bit.tl. Attempts have been made w,gvom'ehts the serelogi- eal rescticone ss meagured by the conglutinating complement Ml‘pgm test (C.C.A.T) with the Joxpogra worm egs count h'nndl and p.fimlmen effects of npcunueuun. Super infection. Puppies naturally infected with T.canis showed marked pesistance to superinfection by doses of 5000 to 20,000 But lorger doses of 50,000 to 100,000 ova eften Resulted in the death of the puppies, It has been shown In this sudy that the immunity soguired from a natural infection can be reinforeed by superinfection with a mode- rate does or 10,000 infective ova to enable the animals to withstand a challenge with a lerge does of 100,000 infective ova. - In_ the puppies supersnfected with large doses of 80000 to 100000) ova most of the existing infection Was not necessarily accompanied by resistence to the re- infection or to its effects, Acguired immunity te J,ognis on in puppies scems to be menifested at least in i wayst (1) by preventing the development of larvee produced by superinfection beyond the second-stage in the lungs their migration to the intestine mainly to produce the fourth stage end (11) by enabling the host to withetand pathological effects of superinfection which are fatal in non-immune puppies, The pathological effect of a superinfection in none Immune puppies is manifested by extenuvp necrosie of the Hepatie parenchymal cells with concomitant inorease of the Serum glutamine pyruvate trengaminese (S0P-T) activity Which are less marked in the immune puppies.
Family and caste in the politics of the sinhalese 1947-1971
(University of Ceylon, 1973-08) Jiggins, Janice
The study begins in Chapter 1 and 2. by examining the nature of the formal political structure in relation to the wider - social environment and noting unigexe features in the consi- tutional and electoral provisions which seem to take certain social factors into account. It is suggested thai areas of elite power other than the legislature are involved in the political decision=making process. In particular, caste and family identities are seen as linking the occupational elites in neo-political groupings which do not necessarily coincide with political parties, and which are capable of influencing policy decisions. Government and administration are seen, to relate to the politics of faction as well as the politics of party and policy. The power structure is posited as one in which the occupational elites (including the legislative) supply the membership of the political elite any one time. Caste and family groups are petites among the occupational elites; caste and family identities and loyalties provide alternative means of recruit- ment to positions of political power and the exercise of poli- tical pressure (other than political parties and ideologies). Chapter 5 attempts a qualitative description of the occupa- tional elites. Chapter 4 exemines the relationship of family groups and kinship patterns to the major political parties and the occupational elites. Given the existence of such family ties, it is asked to what degree they form a stronger bond than, or alternative to, party loyalty. The question whether the family caucus can or does operate politically is examined, in addition, the coincidenceof certain family groups with a particular caste (Goigama) is discussed. Chapter 5 attempts an analysis of the role of caste, both at the constituency and national level, in Ceylon's politics. Beginning with a survey of certain geographic and demographic features in the distri- bution of caste; and their political implications, the effects of the re=shaping of the constituency boundaries in 1945 and 1959 on caste-community voting at General Elections, is examined. An attempt is made to discover the proportional distribution and relationship of each caste group. The results are given of extensive field research undertaken in Sabaragamuwa Province (after island-wide testing of the validity of the attempt and a pilot study of research methods in Matale DKO's division), to establish the proportional relationship of the major caste groups. The political implications are discussed in detail. Finally, the link between caste political behaviour electorally, and the formation and operation of caste lobbies under successive governments, is described; their membership and effectiveness as shapers of policy (rather than merely as political pressure groups) are discussed. The last chapter draws together the threads of the analysis and describes the shifting eckirken of the last twenty-five years in terms of the manipulation ‘of caste allegiances. It shows how the perspectives adopted in this thesis elucidate the persistence of certain family groups (and the continued domi- nanceof the Goigama community) in an era of supposedly popular politics and mass participation.
A study of some aspects of the micobacterioses in Ceylon
(University of Peradeniya, 1974) Pinto, D.D.M.R.M.
In this work an attempt has been made to study some aspects ot the "Mycobacterioses" in Ceylon. The mycobacterioses are infections Produced by the genus Mycobacterium. Mycobacterioses are seen allover the world and many aspects ot these are as yet not investigated or are poorly investigated. These infections pose (special problems in the tropical and developing countries, but the information on these from the latter countries is scarce. The literature on any aspect of the mycobacterial infections in Ceylon is very scanty. The mycobacterioses like any other infections may be examined from two main points ot View: 1.The reaction of the host to the parasite, and 2. The parasite. The reaction of the host to the parasite is embodied in the host's immunological responses to the parasite. These immunological responses may be of the cell mediated component and the humoral component. In this study the cell mediated response has been investigated using the differential (or comparative) tuberculin test, and the humoral response, using Takahashi's antitubercle phosphatide kaolin agglutination test for antiphosphatide antibodies. The differential tuberculin test was done on several population groups in Ceylon, viz. a) Persons of the general. population from rural areas who were not BCG vaccinated, b) Tuberculosis patients, c) BCG vaccinated persons in the general population, and d) Leprosy patients. The test was carried out in all groups using six different PPD antigens derived from Myco. tuberculosis (PPD-S), kansasii (PPD-Y, Runyon's Group I), Myco. scrofulaceum (PPD,Runyon's Group II), Myco. avium (PPD-A) and Myco. batteyii (PPD-B, both of Runyon's Group III) and Myco. fortuitum (PPD-F, Runyon's Group IV). The test technique used was the WHO Standard Tuberculin Test (Mantoux Test), each subject usually being given four PPD antigens. The investigation in the unvaccinated general. population showed that nontuberculous mycobacterial sensitisation and hence infection, was very common in Ceylon, and more common than tuberculous sensitisation. Marked differences in the degree and incidence of nontuberculous sensitisation were found to occur with altitude (the population investigated being at 3 different altitudes, 6,500 feet, 1,500 feet and at sea level), being lowest at high altitude and highest at sea level. No differences in pattern of sensitisation appeared to occur with increase of age (those tested being 12 years of age and above) and in the different sexes, at sea level and at mid altitude, but appeared to occur at the highest altitude. It was seen that at an elevation of 6,500 feet the incidence and degree of mycobacterial sensitisation appeared to increase with age and was greater in males than in females. Differences in pattern of sensitisation were also observed between Sinhalese and Tamils at midaltitude. It was suggested that differences in occupation was probably the cause of the higher degree and incidence of sensitisation seen in Sinhalese, viz. paddy cultivation by the latter. Evidence was produced from the veterinary field, from studies in cattle and buffaloes, in Kenya and Ceylon to support this finding. It was found that sensitisation among the Ceylonese populations tested was commonest to PPDs derived from Runyon's Group II and III organisms and least with Group I and IV organisms. The tuberculosis patients investigated were mostly from mid altitude areas similar to that described for. the general population. It was found that there were both similarities and differences in the distributions of reactions to nontuberculous PPDs between the tuberculosis patients and the general population, from the mid altitude area studied. The possible causes for these are discussed. With PPD-S, the pattern of distribution seen in tuberculosis patients is markedly different from that of the general population group, but similar to that found in tuberculosis patients elsewhere in the world. No differences were found in the distributions of tuberculosis patients of different ages, sexes and of different races. Examination of the pattern of reactions to the different antigens shown by tuberculosis patients showed that clearly larger (dominant) reactions to PPD from Myco.tuberculosis was seen only in 60 percent of pateints.Thus it was concluded that the differential test did not always identifythe mycobacterial infection in tuberculosis patients. Comparison of.............
ලක්දිව දන්ත ධාතුන් වහන්සෙගේ ඉතිහාසය හා තදශ්‍රිත පූජාවිධි
(University of Peradeniya, 1974-10) Vajira, Rev. Kumburugamuwe
Abstract is attached
Mycotoxins in coconut based human and animal foodstuffs
(University of Peradeniya, 1975) Samarajeewa, U.
An attempt has been made in this study to determine the extent of the aflatoxic problem in Sri Lanka with special reference to coconut products with a view to suggesting preventive and regulatory measures for the control of contamination. The study of the extent of the aflatoxic problem was made by first establishing the most suitable method for the assay of aflatoxins in coconut products. Although several procedures have been described for the assay of aflatoxins in various agricultural products there was no established procedure for the assay of aflatoxins in coconut products. A method based on blending with a mixture of chloroform and water. originally devised for groundnuts, has been used by some workers for coconut products. However no data was available on the comparative suitability of this method as regards its extraction efficiency, interference on thin layer chromatographic estimations and convenience. Therefore the existing methods for the various products were restudied with coconuts to establish the best conditions for each method of extraction. The methods were then compared under optimum conditions. All procedures were found to bring about only partial extraction (about 70percent) of aflatoxins. The 70percent aqueous acetone blending procedure w1th lead acetate purification was found to be the most suitable on account of convenience and the purity of extracts which enabled titration without a preliminary column purification. Since a constant fraction of aflatoxin present in a given type of coconut product was extracted by a single homogenization by the aqueous acetone procedure, the application of a correction factor (to replace 2nd and 3rd homogenizations) is recommended, as a time and solvent saving measure~. Application of correction factors for the observed aflatoxin levels has not been described in the literature for assay of aflatoxins. As regards bioassay of extracts, the tadpole bioassay method established earlier for pure aflatoxins was found to be applicable to crude extracts of commercial samples preceded by a short column purification. A field survey was done for the year 1973 to study in detail the extent and origin of aflatoxin contamination in coconut products by examining copra, poonac and coconut oil samples from almost all oil processing mills in different districts during the periods January to April, May to August and September to December. About 50percent of the s~ples collected at random from the firld were found to contain aflatoxins above the maximum permissible level (0.03 ppm in foods for human consumption, suggested by WHO/FAO/UNICEF). The contamination was found to be due mostly to ignorance and negligence during curing and storage of copra. Education of the copra miller and worker, on the economic and toxicological consequences of contamination is of prime importance in the prevention of contamination. Reorganization of the present inspection network in the mills is suggested as a measure for effective control. The economic loss to the industry due to fungal contamination of copra during storage has been estimated earlier to be around 25percent and such control may therefore minimize these losses. Contaminated coconut oil should be diverted for chemical refining or split into glycerol and fatty acids. The contaminated copra should either be steam treated at high pressure or be rejected totally if the contamination is heavy. Investigation into an outbreak of deaths of young goats of an imported breed at Kottukachchiya (NWP) Government goat breeding centre was shown to be due to aflatoxins. The aflatoxins were detected in the feed samples and in the liver tissues and urine of diseased or dead animals. Strains of Aspergillus flavus were isolated from feed samples and were shown to be toxigenic. Identical clinicle features, postmortem appearances and histopathological lesions were produced by experimental feeding of the goats with artificially infected coconut. The factor that contributed to the toxicity of the industrial feed was found to be an ingredient 'polkudu' added in the preparation of the feed mixtures. As there were significant levels of aflatoxins in local coconut products which could cause toxic and trade problems it became necessary to investigate possible methods of prevention of contamination and detoxification of already contaminated samples. Natural and cheap methods were therefore studied for possible industrial application in decontamination. On account of resistance to fungal growth or aflatoxin accumulation described in the literature for various feed products such as groundnuts, sunflower seeds and soybean varieties, different strains of coconuts were studied for their resistance to fungal growth and aflatoxin accumulation by inoculation of grated coconut with different fungal strains under different conditions of incubation and examined at single or several incubation times. No reproducible results were obtained in any of the experiments. The strains of coconut which showed relative resistance on incubation for a fixed number of days showed equal susceptibility on time course studies. The possible reasons for these discrepancies are discussed. The literature on the resistance of other seed products is also controversial, and it is suggested that time course studies of aflatoxin accumulation may minimize errors in such determinations. The applicability to coconut products of the age old practice of smoking for the preservation of foods was studied by inoculating smoked grated coconut, smoked broth media or broth media containing smoked water for its efficiency in inhibiting aflatoxin accumuulation. The treatment was found to inhibit aflatoxin accumulation to a greater extent than mycelial growth. The moisture content of coconut kernels appeared to be critical as moisture levels above 40percent and 15percent supported aflatoxin accumulation in smoke dried and electrically dried kernels respectively. The inhibition of aflatoxin accumulation by coconut charcoal smoke was found to be apparently due to water soluble fractions in smoke as smoked sterile water or broth were also effective in inhibition of aflatoxin accumulation. As spontaneous loss of aflatoxins was previously observed during storage of contaminated coconut the possible cause of the loss were investigated by storing coconut oil under different laboratory conditions. Of the various natural factors studied (heat, light, enzymic activity) only sunlight was found to be effective. The effect was studied in detail. Detoxification of aflatoxins in coconut oil was brought about by subjecting oil in the form of a thin layer of about 2-4 cm. in thickness under experimental conditions to sunlight. The quality (FFA. coolur) of the treated oil was the same as the untreated oil. Pilot plant experiments with the method are suggested for possible adaptation to industrial decontamination. With solid products, copra and poonac, sunlight was not effective in degrading aflatoxin probably because the sunlight did not penetrate solid particles as effectively as through liquid oil. Some strains of Aspergillus flavus isolated from local copra were found to exhibit intense blue fluorescence on hyflosupercel toxigenicity screening plates. These strains were cultured on grated coconut and the metabolites were extracted. A blue fluorescent compound having different but close Rfs with aflatoxins in several TLC solvent systems was isolated. The compound produced fatty changes in the livers of ducklings after oral dosage. The spectral characteristics and the TLC data suggest it to be a hitherto undescribed factor of possible toxicological interest. The lines on which further research in the field of aflatoxins in coconut products are indicated.
Architectural Monuments of Polonnaruwa
(University of Peradeniya, 1975-09) Basnayake, Henry Tissera
In this study an attempt is made to examine the extant architectural monuments (Buddhist) that were erected in Polonnaruva from the time it became the capital of Sri Lanka, to the period of its decline at the end of the 12th century A.D. After a brief introduction in the first chapter, the second chapter sets out to examine the monasteries erected in Polonnaruva mentioned in the literary sources, and to establish their identity with the extant remains as far as possible. The third and fourth chapters present a detailed description of the extant Buddhist monuments, classifying them into building types on the basis of their character and function, with a view to providing an understanding of the architectural features found in each type. Finally in the fifth chapter the architectural components of the different building types are examined in detail comparing them with those of the early period in order to show the architectural traditions existing in ancient Sri Lanka. The conclusion brings out in brief, the main characteristic features of the architecture of the period under survey. Illustrations with maps and‘plates are included in Volume II.
A study of verse narrative in the pali jataka with special references to sections X-XI
(University of Peradeniya, 1977) Dhammapala, Rev. Yatagama
Abstract is attached
ලංකාවේ බෞද්ධ ලෝහමූර්ති (ආරම්භයේ සිට ක්‍රි.ව. 1235 දක්වා)
(University of Peradeniya, 1977-03) Gunarathne, Prangige Seetha Padmini
Abstract is attached
Biosystematic studies of Ceylonese wasps
(University of Peradeniya, 1979) Krombein, Karl V.
Sclerogibba embiidarum (Kieffer), 1925, from Sri Lanke is redescribed, as well as two new species, S. taprobanana from Sri Lanka and S. aridicola from Sri Lanka and South India. 1. The preceding number in this series is "A Monograph of the Ampulicidae (Hymenoptera: Spheccidea)," IN PRESS, Smithson. Contrib. Zool. 298, Members of the Sclerogibbidae ee amigue among Chrysidoidea (olim ethyloidea) in having many more antennal segments than the normal 12 Se 3 and in having nymphs of Embioptera as their hosts. Fenstes (figs. 1-3) annot be confused with those of any other family of aculeate wasps. The seg-eaanenbed antennae and enormously expanded fore femora are unique. 1e winged males are also readily recognized, for they have many-segmented itennae and the fore femora are enlarged though not so greatly as in females. The only sclerogibbid described from Ceylonis Mystrocnemis embiidarum effer, 1925. During my field work in Sri Lanka we collected both sexes of e new species and females of a second new species. Richards (1939) placed five genera in the synonymy of Sclerogibba. obably some of these will have to be resurrected as valid genera when generic reclassification is based on the numerous and as yet unstudied lerogibbids reared by E.S. Ross. Two genera are represented among the Ceylonese species, but I am . icribing all in Sclerogibba because of the uncertain status of Mystrocnemis ‘ffer. Two species known only from females, S. embiidarum and S. taprobanana, belong to typical Sclerogibba Rigg. and Stef.-Perez; both have simple (i.e., dentate) tarsal Claws a bidentate mandibles, and lack a pair of antero- eral pits on the scutum. S. aridicola may belong to Mystrocnemis, a genus ced in synonymy by Richards, but until the unique holotype can be relocated topotypic material made available, certain ambiguities in Kieffer's ginal description cannot be clarified. ‘Both sexes of S. aridicola have ubapical tooth on all tarsal claws, females have tridentate mandibles a pair of anterolateral scutal pits, and males have a small discoidal 1, meking a total of six closed cells in the forewing. The male of crassifemorata Rigg. and Stef.-Perez, the type-species of Sclerogibba,has Simple tarsal claws: and tive closed cells in the forewing, the discoidal cell lacking. The holotype of 6. ehbiYdarn was reared from a specimen of Oligotoma greeniana Enderlein from Colombo, a locality where the annual rainfall is 100-150 inches. My two species were collected in several localities in the Dry Zone where the annual rainfall ranges from 50 to 75 inches. The two males of S. aridicola were collectéd ina Malaise trap, and the females ofS. taprobanana andS. aridicola were found crawling on the ground among leaf litter. Three species of Embioptera were collected - a yellow pan trap placed among leaf litter at Palatupana, where both female species were collected. The former were Oligotoma humbertiana (Saussure), QO, saundersii (Westwood) and Apothonia ceylonica (Enderlein); all of these are otentialoy 3 Pp hosts of the two sclerogibbids. Considering the cryptic habitats preferred.by sclerogibbids, I believe that other species still remain to be collected in Sri Lanka, particularly in the Wet Zone areas of much higher rainfall.
Chemistry of some novel friedelane triterpenoids from Kokoona Zeylanica THW.
(University of Peradeniya, 1980-10) Nanayakkara, N. P. Dhammika
This thesis is composed of two parts. The first part consists of the isolation and structure elucidation of eleven friedelane derivatives from Kokoona zeylanica Thw. of the family Celastraceae. Of these, eight compounds were found to be new, belonsing to three series according to their oxyrenation pattern. The kokoondiol series consisted of three compounds namely kokooniol (friedelan-4-one-27-01), kokoononol(friedelan-3,?1-dione~-27-01) and kokoonol (friedelan-3-one-21a,27-diol); while the zeylanol series contained three comrounds, zeylanol (friedelan-3-one- 6p-ol), zeylanonol (friedelan-3,?1-dione-6f-o1) and zevlandiol (friedelan-3-one-6P,21P-diol); kokzeylanol (frieéelan-3-one-6p, e7-diol) and kokzeylanonol(friedelan-3,21-dione-6p,27-diol) constituted the third series, the ‘okzeylenol series. The compounds belonsing to each series were coemically interrelated and their structures were determined with the help of srectrosconic data. FPhotolysis of those containing the Pl-keto rroup sided not only the locstion of this group but also the determination of the C-27 hycroxy function. In their chemical correlstions two recently described reiuction methods were applied to deoxyrenate S-h roxy,cl-hydroxy and 2?-hydroxy function. In the second part of this thesis the assirnment of the C-13 n.m.r. siennls of nine compounds friedelin, frieéelan-2l-one, friedelan-6-one, friedelan-27-ol, friedelen-3.21-dione, friedelan-3,6-dione, friedelan-3,6,°l-trione, friedelan-3- one-27-ol (kokoonol), friedelan-3,21-dione-27-o1 (kokoononol1) are discussed. The partially relaxed fourier transform (PFRT) Spectra and lanthanide induced shift (LIS) data were used in the assignment of the carbon atoms of these comrounds.
A Re-assessment of the bacteriological clinical and immunological features of typhoid in Sri Lanka
(University of Peradeniya, 1981) Thevanesam, V.
Typhoid fever, caused by Salmonella typhi, is endemic in many parts of the technologically underdeveloped world including Sri Lanka; it results in high morbidity with a mortality of 2 - 3per cent. The diagnosis of typhoid depends on the recognition of its clinical features, serological tests and definitively, on the isolation of Salmonella typhi from body fluids or tissues. A change in the clinical presentation of typhoid has recently been reported. This study of the clinical features in patients with bacteriologically proven typhoid showed that a mild febrile illness with headache, intestinal symptoms (especially diarrhoea)occurred frequently. Rigors were not uncommon and should therefore not exclude a diagnosis of typhoid. Hepatosplenomegaly were the only physical signs which were detected with any constancy. Unusual presentations were not seen in our patients. The clinical picture of typhoid was however not sufficiently distinctive to permit of a definite clinical diagnosis. Complications were uncommon. Isolation of Salmonella typhi from patients' blood by both clot and whole blood culture gave comparable results. Isolation rates from blood and faeces in patients with a tentative diagnosis of typhoid (on clinical features and serological reactions) were low. Strains isolated from our cases confirmed with the typical morphological, cultural, biochemical and antigenic properties described for the species. Fifty percent of the Vi + strains were of phage type E1 with approximately 25per cent of Vi or with degraded Vi, suggesting that phage typing would not be of much value in epidemiological studies. All the strains were sensitive to chlora~ph8nicol by the disc diffusion method, with MIC values in the tube dilution tests ranging from 2.5 to 10ug/ ml,(values reported from other studies lie between 0.75 5ug/ml). The serological diagnosis of typhoid is useful in the diagnosis of typhoid fever particularly in countries with inadequate facilities for the isolation of Salmonella tvphi. A study of the '0' and 'H' antibody titres in patients with bacteriologically proven typhoid and in control subjects (healthy volunteers and patients with non-typhoidal illnesses) showed that antibo dy titres are significantly higher in patients with typhoid. '0' antibody titres of over 1:240 could be used with 92per cent confidence as a diagnostic criterion of typhoid if either blood culture is either not available or negative. The 'H' antibody titres were less helpful, false negative results having been obtained in approximately 30i.0f patients. Basal antibody titres were found to vary considerably between the healthy volunteers, normal blood donors and conservancy labourers although these subjects were from the same geographical area. A study of the Cell Mediated Immune Response (CMIR) to Salmonella tvphi antigens in patients with typhoid fever was done using the leucocyte migration inhibition test and a crude extract of antigens from Salmonella tvphi. An antityphoid CMIR developed a significant number of patients with bacteriologically proven typhoid fever. The duration of the clinical illness and occurrence of complications could not be correlated with the development or absence of a CMIR. There was also no correlation between the '0', 'H' and 'Vi' agglutinin titres and the development of an antityphoid CMIR in the typhoid patients. Two groups of control subjects (healthy volunteers from the general population and conservancy labourers) were also studied concurrently with the patients for their humoral and Cell Mediated Immune Response to Salmonella tvphi. Patients with typhoid had a significantly higher incidence of an antityphoid CMIR than healthy volunteers but no difference was found between the positivity rate in patients and in conservancy labourers, probably on account of the latter's occupational exposure to human faeces which may have contained Salmonella tvphi. The Humoral Immune Response (HIR) and CMIR were also studied in two groups of normal volunteers (members of the general public and conservancy labourers who had no previous history of typhoid or antityphoid vaccination), before and after subcutaneous (SO) and intradermal (ID) immunisation with heat killed - tricresol preserved TAB vaccine to determine the efficiency of the vaccine in inducing an antityphoid CMIR. In the first study, a significant antityphoid CMIR was demonstrable in both se and ID vaccinated subjects though here was no significant difference between the two groups. The liability of the CMIR inducing antigen(s) was suggested by the reduction of the rate of CMIR induction with ageing of the vaccine. In the second study done with a fresh vaccine over a shorter period of time, the development of a significant antityphoid eMIR was confirmed. Post immunisation energy in the Cell Mediated I~~une Response was seen after both SC and ID immunisation, in both studies and may partly explain the development of provocation typhoid.
Some growth phenomena in Apple (Malus Domestica L. Dorkh) grown under tropical highland conditions of Sri Lanka
(University of Peradeniya, 1981) Herath, Herath Mudiyanselage Edward
Early investigations on apple cultivation In the dry mesothermal regions of the highlands of Sri Lanka showed that some apple cultivars could be grown for commercial exploitation with certain modified cultural practices. Using elevation to vary temperature, it was found that critical temperature and moisture regimes existed to make the apple tree fruitful. Although climatic conditions at the latitude and altitudes hours of low temperature at or below 7.2°C, buds of some cultivars emerged out of rest at much higher temperature at a higher elevation location (1666 m) with complete leaf fall in December and normal flowering in March. At the mid elevation location (1303 m) , where defoliation was partial, modified training, pruning and the use of a defoliant produced satisfactory results. Low temperature treatment of a continuous nature as reported elsewhere was almost non-existent under local conditions. Low moisture and cumulative "chilling" in the form of low night temperatures appeared to trigger the fruit bud initiation process within three months of exposure to such conditions. There were differences between cultivars in their response to climatic regimes. There were also substantial differences in fresh weight of buds during the seasons at two elevations tested,giving credence to the fact that some changes in growth take place even when buds appear dormant. An anatomical study of buds sampled from Halgran Oya (elevation 1666 ml and Rahangala (elevation 1303 ml revealed one flowering peak for the former and two flowering peaks for the latter. Developmental stages of flower buds for the major flowering season (December-March) revealed that there were generative buds at different positions of young and old shoots. These buds were however at varying degrees of development and completion of these stages take place during the dry season from June to August, especially at Rahangala. True leaves as well as scale leaves protecting buds appeared to control activity of buds. When sufficient scale leaves were removed to expose the greener ones closer to the floral initials the apical bud resumed growth, in the presence of the upper half of true leaves below the apical bud, activity of buds in the Immediate vicinity were controlled. Removal of scale leaves from swollen axillary buds too had a stimulating effect on some of them as well as buds closer to the treated ones. The removal of scale leaves of the apical meristem either mechanically carried out or chemically removed gave the best results. Comparing the effects of 4-6 dinitro .-ortho-cresol (DNOC) as a defoliant and urea as a direct feeder of nitrogen to shoots of apple given as a spray or spot application to different portions of the shoot, showed that DNOC was far superior to Urea in the activation of a greater variety of buds. DNOC appeared to play the role of more than a defoliant. The modes of action of these two chemicals also seemed to vary. In a subsequent study| bearing apple trees were sprayed with DNOC, GA33, CCC and Ethrel at the mid elevation experimental station at Rahangala to study the effects on growth phenomena. DNOC produced a uniform growth flush with flower buds opening in old as well as new shoots. Ethrel produced a spectacular growth phenomenon where terminal and axillary buds of young and old shoots opened whilst physiologically active leaves remained intact. There was a slight shortening of internodes of new shoots induced by the application of CCC. The GA3 was ineffective at the concentration it was tested, and mechanical defoliation simulated the effects of delayed foliation,1 very characteristic of apple grown in the lower latitudes of the temperate zone where warm winters are occasionally experienced. In a study of stock-scion interaction with five scions grown on two rootstocks, growth was found to be generally controlled under local conditions. Prairie Crab, a seedling rootstock gave larger trees than Northern Spy, a clonal rootstock, irrespective of the scion used. The highest cropping intensity was recorded in Rome Beauty and Ragala Apple on Prairie Crab rootstock but the best ratio of crop to tree size was Rome Beauty when grafted on Northern Spy stock. Rootstocks also appeared to affect fruit quality. Using leaf analysis to determine nutrient status, in another comparison of five scion cultivars in relation to season and stock-scion combination the most suitable period under Rahangala conditions for leaf sampling was found to be from mid February to mid March. This was true for Nitrogen, Phosphorus, Potassium, Calcium and Magnesium. The periods of nutrient stability however varied slightly for each element studied. Foliar diagnosis was found to be an excellent tool for the study of nutrition of apple.
New chemical constituents from some endemic flora of Sri Lanka
(University of Peradeniya, 1981-10) Surendrakumar, S.
This thesis is composed of three parts. The first part consists of the isolation And structure clucidation of a new class of some novel polyphenols of resveratrol Origin (3,5,4'=trihydroxy— stilbene) from some endemic Dipterocarpaceae. The presumed formation of these compounds by phenolic coupling reaction And their viosynthesis is also ty discussed. Data obtained in this study also uzgest that these oligomers of resveratrol have pronounced antibacterial activity and could be used as taxonomic markers on a familial Level to Dipterocarpaceae, 13 nell.er. data of these compounds are interpreted and thelr unique mass spectral fragmentation are studied as far as possible, The second part describes the isolation and characterization of some new constituents from some endemic species of the family Moraceae. ‘The isolation and structure clucidation of two new chromenodihydro= benzoxanthones from_Artocarpus nobilis Thw. are the first examples of the presence of benzoxanthones in pienis. These two new natural products further enlightene a route to the biosynthesis of xanthones from flavonoids which still remain obscure. ‘he structure is also ieoposed for a new prenylated flavonoid from this species. Te presence of resorcinol in this species is reported for the first time and making it the third Artocarpus Species showing the presence of this compound. Three New minor alkaloids have been isolated from Broussonetia : Zgeylanica and two of them have been shown to Have a 8-hydroxy~quinoline moiety and the other Is a bipyridine diol. As a completion of the endemic survey Of this Temily the chemicel constituents of endemic Ficus species are also studied in this part. Part three is based on the chemical investigation Of Caloohylluin calaba L. var. worthingtonii Stevens a plant Belonging to the family Guttiferae. A Giprenyloted trioxygenated xanthone, isolated, Is found to be the precursor of the major xanthone in this species.
Secondary school teacher personality characteristics as perceived by students teachers and principals
(University of Peradeniya, 1982) Kularatna, N. G.
Personality characteristics contributing to effective teaching has been a subject of considerable research during the last few decades, These studies have taken several forms. Certain studies have sought to determine characteristics perceived to be desirable for effective teaching by teachers themselves and others closely related to teachers. Some studies have attempted to determine characteristics related to effective teaching by seeking to correlate various measures of teaching efficiency with assessments of various personality characteristics. There have also been attempts by certain “investigators to identify characteristics of effective teachers under experimental conditions. The present investigation was a teacher characteristic perception study. It was concerned with the personality characteristics perceived by principals, teachers and students to be desirable for secondary school teachers. It's specific objectives were to identify characteristics perceived to be desirable for secondary school teachers, to determine their relative and absolute importance as perceived by above eroupe of subjects and to discover consensus within and across different groups of subjects regarding their pe ceptions. "The principals, teachers and grades 10 and 11 pupils in the secondary schools of Kandy Education Region formed the basic population that came under the purview of this investigation. Three samples of 72 principals, 300 teachers and 320 students were drawn from a stratified random sample of 40 urban and 40 rural schools. An instrument embodying 25 teacher personality characteristics or traits was developed to measure the perceptions of the selected subjects. This instrument consisted ‘of three parts. First part was designed to elicit personal information about the respondents. Second part was designed to measure the subjects’ perception of the absolute_ importance of each of the selected traits using a five point Likert rating, scale. Third part of the instrument was designed to measure the subjects! perceptions of the painters importance of selected traits, using the method of paired comparisons. Perceptual data thus derived was subjected to statistical analysis using certain statistical technicues. These techniques included the computation of Spearman's rank correlation coefficients between the trait rankings of different groups of subjects, ¢omputation of Kendall's coefficient of concordance among the traits rankings of several groups of subjects, computation of the arithmetic means and the standard deviations of the weighted rating scale scores in respect of each trait for each group of subjects. Tests of significance employed consisted of the tests of the significance of Spearman's rank correlation coefficient, Chi square tests, Mann Whitney tests and t tests. This study revealed that all traits which came under the purview of this insuiry had been perceived to be of significance for secondary school teachers, by all principals, teachers and students sampled in this inquiry. Certain marked similarities as well as discrepancies in the perceptions within and across different groups of subjects were also found to occur. These peculiarities in the perceptions of subjects appeared to be related to differences in their needs, role specifications, peeanteoce of the objectives of education and personal backgrounds. This investigation spot-lighted the dearth of teacher characteristics research in Sri Lanka. It also revealed some probable lines of inquiry for future research in this area.
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
Vaccination of animals against infection
(University of Peradeniya, 1983) Chusattatayanond, W.
Normal infections of the filarial parasite, Brugja pahangi, in jirds (Meriones unguiculatus) were studied to compare the results of the subcutaneous and intraperitoneal routes of infection, the responses of. the two sexes and to determine the number of animals to be used in each group in tile subsequent experiments. The possibility of developing a vaccine against filarial infection was investigated using the B. pahangi-jird model. The experiments involved the use of 'non-living and 'living' vaccines. Non-living vaccines were a somatic antigen which Has derived from adult worm homogenates and a metabolic antigen which had been released by adult parasites during in vitro cultivation. Living vaccines were the live infective stage of the parasites attenuated either by radiation from a Cobalt 60 source or by the chemoprophylactic use of the broad spectrum anthelmintic flubendazole. The level of resistance in jirds was determined by the reduction of both number and size of the adult worms recovered after challenged with known numbers of infective larvae. Non-living vaccines were found to be unsuccessful in producing protection. Live-attenuated vaccines were shown to give more promising results. Jirds receiving irradiated infective larvae which had been exposed to different levels of radiation all showed some degree of resistance. More interesting results were obtained from ,the experiments with flubendazole. The drug itself was shown to have excellent prophylactic activity and jirds receiving infective larvae during the period of drug activity showed a significant level of resistance against reinfection "When subsequently challenged. ELISA was used to detect specific antibody against antigen derived from crude soluble extract of adult Harms (CSE) during the course of infection in every experiment. Peroxidase - conjugated rabbit anti-hamster IgG obtained from commercial sources was used. It was found that IgG level against CSE had no correlation with the level of resistance found in vaccinated jirds.
the Emerging role of joint farming in the Agricultural development of the developing countries with reference to Sri Lanka
(University of Peradeniya, 1983) Shanmugaratnam, Nadarajah
The present stage of agrarian transition of the less developed or developing countries has to be viewed in the context of the more or less well established goals of development such as economic growth, employment, self reliance and popular participation. The two types of production, plantation and peasant agriculture, found in many countries like Sri Lanka have become outdated in a modern world in which three types of farming organizations are emerging. They are the large scale mechanized farm which is run like an industry, the modern family farm and. the multi-family or joint or collective farm. All three are highly profit-motivated and market- oriented in the market economies. The first and the third constitute the major forma of farm organization in the centrally planned economies. The developing countries, in order to achieve their goals of growth with equity should opt for an agrarian set up that would enable a more even economic development. The individualized peasant farming that characterizes the major part of tho agricultural economy of tho less developed countries like Sri Lanka. is generally backward. All attempts at modernizing the peasant sector have been directed at transforming the individual peasant farm into a modern family farm. The results have been highly disappointing. Even the limited growth achieved has been largely confined to a minority of the farmers. Tho continuation of this trend has led to an uneven economic development in the peasant sector. The situation baa predicated a need for alternative forms of farm organization. In their search tor models of reorganization several developing countries ha...e chosen joint farming, as one of the possible w~out, to achieve the goals of development. It has been shown here, that joint farming is not a monopoly of the c.centrally planned economies. In the developing market economies two tendencies may be discerned as regards joint farming. One, is motivated b.1 purely techno-economic considerations such as more efficient land and water use. standardization of techniques and diffusion of technology. more effective use of supportive institutions etc. The other has been motivated by an overt political-ideological commitment to transform the entire rural economy towards a more egalitarian system. which is described by the governments concerned as socialism. An economic case for individual small holding. hall been built by certain agricultural economists on the basis of limited and highly controversial empirical evidence that output per acre is higher in the small farm than in the large farm. The argument is supported by the fact that modern bio-chemical technology is highly divisible, and therefore a scale neutral. This line of thinking justifies re distributive land reform aimed at creating individual small holdings from all. economic standpoint.. It has been shown in this thesis that there is no economic ca Be for the individual small holding from a national standpoint in the context of the goals of development stat.d earlier. The efficiency shown by some individual small holdings in terms of output per acre does not provide all. adequate basis for a generalization. Moreover, we have pointed out that even the empirical base used by the proponents of the small family farm as the way out for the developing countries is itself weak and controversial. The major factors that contribute to the uneven development in the developing countries in general, and Sri Lanka in particular are discussed in this thesis. Institutional deficiencies, ecological factors, an uneven farm size structure and individual variations in economic and entrepreneurial capacities have through their joint and cumulative effects thwarted the hopes of growth with equity.It is in this context, the role of joint farming as a transitional mode of production to achieve the development goals has to be assessed. Our analysis of the agrarian situation in the peasant sector of Sri Lanka shows that it conforms to the general pattern of uneVeD and inadequate development that is observed in the developing countries. sri Lanka's experience in dry zone colonization of land does not necessarily lead to an even economic development and distribution of income. In fact the evidence available overwhelmingly shows that uneven development is the rule in the colonization schemes due to inequalities in several other fundamental factors such as accessibility to institutions, initial economic streagth, entrepreneurial skills, availability of irrigation water etc. Within sri Lanka's peasant sector the farmsize structure is uneven over a range of 0 - 10 acres and the age-old tenurial practices continue to exert a considerable impact. The smallness of the farm and the· other above mentioned factors of heterogeneity prevent a balanced use of resources at the farm level. In the dry zone, water management and land use call for group action. In the wet zone soil conservation and catchment preservation call for joint efforts by small and large holders. The structural dualism between plantations and small holdings has contributed an obstacle towards an integrated approach to development. The imperative of economic and social integration of the plantation and the peasant sectors. compel.. an evolution of the peasant sector towards larger production units and diversification. This could be best achievd through joint farming, which may begin with group action elementary levels and progress through consolidation at the land use level to higher stages of integration and co-operation. Based on the social, economic and agro-ecological conditions in the two major climatic regions. viz: dry and wet zones. and the continuum of joint farming constructed by us on the basis of international experience. re-organization models have been outlined The main areas of co-operation in the prescribed initial phase of the models are in soil and water management. production programming, land preparation, crop management and investment on non- divisible innovations and infrastructure, group credit and a collective approach to extension and community development bave been stressed. The econollic potentials of joint action are very high, but the level of auccess in economic terms would depend on the social organization of the producers and the invisitutional support. It is pointed out that in the current period after land reform, the techno-economic need for joint farming is even greater. This is due to the possible dangers the small farmers would face from larger farmers, in a competitive market economy as it developes. The survival of the small farmers as farmers, can be assured only by group action.

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