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FS98, a grade IV strain of myxoma virus, was found to be suitable as an immunising virus for wild rabbits in Australia and suitable for introduction as a biological control agent into a wild rabbit population with the flea Spilopsyllus cuniculi (Dale) as vector. The Nottingham attenuated strain was found not to be a suitable virus for immunising wild rabbits. Seven samples of virus taken from the field in Australia and assessed as grade V virulence in 1965 were more virulent when reassessed in 1976. Possible misclassification by chance was examined by means of randomly selected survival times from actual data and rejected as a complete explanation. Testing with a wide range of different mixtures of a cloned highly virulent and a cloned attenuated strain of virus failed to support, but did not exclude, the idea of changes in virulence grading being caused by differential survival in mixtures during storage. ADDITIONAL ABSTRACT: Strain FS98 of myxoma virus, isolated in Australia in 1967, was suitable for immunizing wild Australian rabbits by means of infected fleas, but the Nottingham attenuated strain was unsuitable. Strain FS98 was of grade IV virulence in the scale of Fenner & Marshall (1957). Changes in virulence during prolonged storage were discussed.

The age-structures of rabbit populations at 4 climatically different sites in South Australia were found to have altered significantly since the introduction of Spilopsyllus cuniculi (Dale) as a vector of myxomatosis. The ratio of young of the year to older rabbits in summer was greatly reduced. There was evidence of decreases in size of all observed populations and (for 1 population) in ability to increase rapidly in favourable years. The ratio of young of the year to older rabbits was a convenient and sensitive index of changes in population structure; for analytical purposes, the log transformation (ln [ratio] or ln [ratio + 1]) was biologically and statistically sound. Since the fleas became established, field-strain viruses may have become more virulent and morbidity rates may have increased, but the factors enabling rabbit fleas to enhance myxomatosis as a cause of mortality are unknown. The apparent virulence may have increased because of selection for viruses of high virulence, which are best suited for transmission by S. cuniculi, and possibly because the dose of virus transmitted by fleas is considerably greater than that by mosquitoes or other agents.

1 Introduction -- 1A General remarks -- 1B Classification of organisms -- 1C Lipid nomenclature -- 2 Major Lipid Types in Plants and Micro-Organisms -- 2A Fatty acids -- 2B Acyl lipids -- 2C Terpenoids -- 2D Sterols -- 2E Other lipid types -- 2F Ether lipids -- 3 Distribution of Lipids -- 3A Lipid distributions in different organisms and their use in taxonomy -- 3B Subcellular distribution of lipids -- 3C Intramembrane lipid distribution -- 3D Subcellular fractionation and membrane isolation -- 3E Factors affecting the lipid composition of plants and microorganisms -- 4 Biosynthesis -- 4A Fatty acids -- 4B Acyl lipids -- 4C Terpenoids and steroids -- 4D Complex lipids -- 4E Ether lipids -- 5 Degradation -- 5A Degradation of acyl lipids -- 5B Oxidation of fatty acids -- 6 Lipid Functions -- 6A Membrane structure and function -- 6B Storage -- 6C Microbial lipids as virulence factors -- 6D Conclusion -- Further reading.

The growing importance of third world countries in the international system brings their potential for conflict and cooperation to the forefront. Given the fact that the East-West conflict tends to intensify the North-South conflict, a general tendency toward more warlike antagonisms is becoming evident within the Third World. In view of this trend, Latin America as a region becomes particularly interesting; conditions here have always led to conflict situations between the various countries, but specific historical factors seem to have kept these conflicts from erupting to the same extent that they have in other regions of the Third World.Conflicts between two states do not suddenly occur. Their virulence rather gradually develops from a mixture of border conflicts, historical animosities, economic disputes, differences in political systems, arms races, and certainly, the influence of the big powers.

AbstractMilitarism. The word has a faintly anachronistic ring. It conjures up images of Prussia in Bismarck's day, or perhaps Hitler's Third Reich. It suggests a static, rigid society in which a traditional officer caste dominates an authoritarian and hierarchical state system. But while this image is still valid for many societies today, it fails to convey the particular virulence and dynamism of modern militarism—a scourge that threatens to obliterate all the gains made in the areas of human rights, democratic government, and economic progress throughout the world since the end of World War II. If not checked soon, this scourge will almost certainly trigger a global conflagration that could destroy the human species.Consider: World military spending in 1977 reached the record level of $400 billion—more than the combined gross national product of the world's hundred poorest nations. Most of these funds, of course, were expended by the two superpowers, which now have sufficient nuclear weapons to destroy each other several times over.

For the past twenty years the South American republic of Colombia has suffered from a social phenomenon of such magnitude that it has defied not only the contemporary jargon of sociologists and political scientists but even the time-honored terminology of insurrection, rebellion, riot and revolution. Perhaps because the only element of this phenomenon that all observers can agree upon is the fact that it is and has been eminently violent, it has come to be called simply "la violencia," or "The Violence."The phenomenon known as la violencia never has been completely absent from Colombia since 1946, but it has had two periods of particular virulence, the first between 1948 and 1953 affecting the departments of Tolima, Boyacá, Cundinamarca, Antioquia, Valle, Caldas, Cauca, Santander del Sur, Arauca, Huila, Chocó, Caquetá, Meta, Casanare, Vichada and Bolívar, that is, the entire country with the exception of parts of the Atlantic coast and the southernmost department of Nariño.

Excerpts from a statement delivered at a session of the Amer Jewish Congress & first printed in the Congress BiWeekly are presented. It is noted that 'in many respects the black power movement is chaotic & diversionary.' But the various groups & individuals seem to have the following beliefs in common: (1) they place their emphasis upon the desirability of some form of racial separation as the way of obtaining racial justice in the US; (2) they assert some degree of rejection of whites & white participation in the civil rights struggle; (3) they express an increasing tendency to verbalize varying degrees of resentment against whites in general-varying from extreme & overtly expressed anti-white feelings to indications that whites in general have not been serious in their involvement in the struggle for racial justice; (4) they hold a romantic & chauvinistic belief that the Negro can obtain power & racial justice in the US through his own efforts without regard to the extent of alienation or isolation from whites. Some of the black-power advocates assert that the greater the extent of isolation & alienation of Negroes from whites, the greater the chances of their obtaining some form of undefined racial justice. This indicates that the black-power movement is essentially a racist movement which rejects integration. Black power advocates & white segregationists share the belief in the magic of race & color & the attitude that democracy can function effectively under a system of racial segregation. The problem cannot be remedied by the blind-alley approach of the black nat'lists who insist upon allblack Sch's in all-black communities. The combined thinking, energy & commitment of Jews, Catholics, Protestants, of whites & Negroes, is required to develop & implement immediately an effective program to improve the quality of educ. The Jews & whites must not withdraw from the struggle for racial justice. 'Those black nat'lists who seek to pre-empt this struggle for themselves betray the fact that they are among the most pathetic victims of the virulence of Amer racism.' M. Maxfield.

Hunter kill records maintained by the Virginia Commission of Game and Inland Fisheries have indicated that continuous declines of cottontail rabbit (Sylvilagus floridanus) populations have occurred in some areas of Virginia since the early 1930's. This study was undertaken to determine the factor(s) responsible for these declines. The Fort Pickett military reservation in southeastern Virginia, where declines in rabbit harvest were documented, and the Radford Army Ammunition Plant (R.A.A.P.) in southwestern Virginia, known to support relatively high rabbit populations, were the study areas for this investigation. From aerial photos, it was found that little measurable change in rabbit habitat occurred at Fort Pickett between periods spanning known declines in rabbit harvest. Edaphic, meteorologic and vegetative comparisons between areas indicated higher soil pH and magnesium levels at the R.A.A.P. than at Fort Pickett; higher mean monthly temperature and rainfall at Fort Pickett than at the R.A.A.P.; and little difference in vegetation and cover characteristics between the two areas. Over four times as many trap nights were required to capture rabbits at Fort Pickett as at the R.A.A.P. Comparisons in physiologic and disease parameters of 164 rabbits, 82 from each study area, were made. Over 30 physiologic measurements were recorded from individual rabbits. These measurements included, body and organ weights, fat condition indices, and reproductive and hematologic measures. Twenty-two individual parasitic and infectious diseases were found. Rabbits were infected with from 5 to 14 species of pathogens. Several species of parasites attained significantly greater infections at Fort Pickett than at the R.A.A.P., and six species of parasites attained higher infections at the R.A.A.P. than at Fort Pickett. Several species of parasites attained higher infection levels than any known previous reports. Area, sex and season comparisons of physiologic and disease measurements are presented. In comparison to the R.A.A.P. rabbit population, the Fort Pickett population was found to have high energy stores but low body and organ weights, low total serum proteins, low serum albumin levels and high eosinophil counts. The Fort Pickett population was also found to have extremely low natality. Optimum conditions appear to exist at Fort Pickett for several parasite species and it is postulated that parasitic disease was limiting the productivity and rate of increase of rabbit populations at that locality. Serologic survey of 198 rabbits for tularemia (Francisella tularensis) antibodies was conducted. Five rabbits had agglutinins present. One of these was collected at the R.A.A.P. and four were collected at Fort Pickett. A severe decline in rabbit numbers was seen at Fort Pickett in the summer of 1974. This decline is postulated to have resulted from an epizootic of tularemia. New evidence is presented for a disease virulence theory of tularemia. It is postulated that a low rate of increase in rabbit populations in Virginia and recurrent epizootics of tularemia have been responsible for continuous declines in hunter harvest. ; Doctor of Philosophy