The main purpose of the study was to produce a population forecast by sex and one-year age groups for the Republic of Azerbaijan for the period 2009-2050. The forecasting process consisted from the several stages, which are included in the general structure of the production process of a forecast. During the data analysis, a number of methods were applied: redistributional methods of intensities, method of reconstruction abridge life tables into complete life tables, application of the Kannisto method to describe mortality in the old ages. The estimated one-year intensities were utilized in the current trends analysis serving as a background for forecasting the parameters of the cohort-component projection model. During the population forecasting the cohort-component projection model was used and population was forecasted in three scenarios (variants). Underlying assumptions were based on analysis of the recent demographic trends and an assessment of their implications for future changes. Keywords: forecast, population development, Azerbaijan

Development of population of Staňkov in 19th century Abstract This work focuses on description of population development in Staňkov in years 1827-1900. Data were gained by the method of anonymous excerption of registers of births, deaths and marriages. These registers are currently located in State regional archive in Pilsen. Staňkov always had a Czech majority, even though it is located in Western Bohemian region close to German boarder. Inhabitants of Staňkov worked mainly in agriculture and trades. Great development in industry and mining took place in Staňkov in the analyzed period. Population development is analyzed from the point of view of fertility, mortality and nuptiability. The results from Staňkov are also compared to other towns in the same time period. Keywords: historical demography, 19th century, development of population, Staňkov

Mortality in eiders (Somateria mollissima) on the Ythan estuary, Aberdeenshire, and elsewhere, has been claimed to be associated with the spiny-headed worm, Profilicollis botulus. Eiders acquire the disease by eating crabs (Carcinus maenas) infected with the cystacanth stage of the parasite. A detailed quantitative study was undertaken to elucidate some of the factors which control the abundance of the parasite in its intermediate and definitive hosts. During 1979-81 the P. botulus burdens in eiders and crabs were regularly monitored. Eiders were either taken alive off the estuary, or off the nest, and sacrificed, or found dead on the shore line. Crabs were caught in traps at two sites on the estuary. Female P. botulus in eiders were assigned to one of five categories according to the state of development of the eggs contained within their pseudocoelom. To estimate the size range and numbers of crabs eaten by eiders, crab chelipeds, or parts of chelipeds, were recovered from eider faeces collected monthly from roost sites. Regression equations relating certain cheliped dimensions to crab carapace width were used to estimate the size range eaten. The numbers of chelipeds per unit weight of faeces, equivalent to the quantity excreted per eider per day, was used to estimate the numbers of crabs eaten. Daily P. botulus infection rates in eiders were calculated by combining the quantitative data on crab intake by eiders with the cystacanth burdens in the crabs. Captive eiders, reared from eggs, were used to determine the age, days post-infection, of the five categories of female parasites. These development times were combined with the burdens found in the eiders sampled from the estuary to produce a static life-table of the mortality of female P. botulus. From this, estimates of the parasite's establishment rate, mortality rate and lifespan were obtained.

Egg weight and fecundity of Clyde spring-spawning and autumn-spawning herrings, Clupea harengus L., in the nothern North Sea and North Minch in different years were analysed. For Clyde spring-spawning herring high variation in egg weight was found and it was attributed to more than one spawning group spawning in the area. Annual variation in fecundity between 1963-1984 was found. Fecundity in 1984 was found to be about 10% higher than previous years. For autumn-spawning herring, fish spawn in the North Minch produce about 1.18 times heavier eggs than those spawning in the northern North Sea. Regional annual variation in fecundity between 1971-1984 was found. In 1984 fecundity of samples collected from Shetland was 1.12 higher than those of North Minch. Fecundity indices for Shetland samples were found to be 1.23 to 1.77 higher in 1984 than 1971-1973. Annual variation between 1971-1973 was also found. It was concluded that fecundity is a potential contributor to population regulation not necessarily related to population density. Monthly analysis of energy content of soma and gonad was carried out for Clyde spring-spawning herring. Differences in the magnitude and timing of energy allocated to the gonad was found between sexes. Energy budget was prepared for each sex at ages 2 and 3. No deficient of energy during winter was apparent due to gonad maturation and metabolic activity. Routine metabolic rate was measured in a group of herring in a respirometer. Oxygen consumption was estimated to be 31.3, 93.3 and 278.6 mgO2 kg-1 h-1 at 5, 10 and 15oC respectively. Standard oxygen consumption was derived from oxygen consumption and theoretical swimming speed to be 20.4, 59.5 and 164.8 mgO2 kg-1h-1 at 5, 10 and 15oC.

No description available.

This study lnvestigates the effect of the late Cenomanian Oceanic Anoxic Event (OAE) on the planktonic and benthonic foraminifera. On the former, the OAE was the cause of major extinctions within the population, the return to pre-OAE oxygen levels permitting recolonization of the vacated niches. On the latter, the OAE caused extinctions but resulted in a low oxygen tolerant fauna which slowly evolved into the vacated niches on the post-oAE recovery of oxygen levels. The changes in the foraminiferal populations have been integrated With changes in other marine organisms through the late Cenomanian.

Call number: LD2668 .P7 1973 H53

In this research report I address the question: Is it ever morally justified to cull elephants? And, if it is, what criteria need to be fulfilled for a cull to be morally justifiable? In answering the first part of the question, ‘Is it ever morally correct to cull elephants?’ I defend the claim that the killing of elephants is a pro tanto wrong. The second part of the question, ‘What criteria need to be fulfilled for a cull to be morally justifiable?’, directs my attention to identifying conditions under which the pro tanto wrong of killing elephants could be outweighed by other moral considerations. I identify and critically discuss these criteria, developing what I call a ‘Theory of a Just Cull’. Finally, I apply my Theory to the current situation in South Africa, and argue that it is not possible to ethically justify elephant culling in South Africa in the current circumstances.

A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy February 1976 / This thesis treats systems of ordinary differential equations that ar*? extracted from ch-_ Kolmogorov forward equations of a class of Markov processes, known generally as birth and death processes. In particular we extract and analyze systems of equations which describe the dynamic behaviour of the second-order moments of the probability distribution of population governed by birth and death processes. We show that these systems form an important class of stochastic population models and conclude that they are superior to those stochastic models derived by adding a noise term to a deterministic population model. We also show that these systems are readily used in population control studies, in which the cost of uncertainty in the population mean size is taken into account. The first chapter formulates the univariate linear birth and death process in its most general form. T i«- prvbo'. i: ity distribution for the constant parameter case is obtained exactly, which allows one to state, as special cases, results on the simple birth and death, Poisson, Pascal, Polya, Palm and Arley processes. Control of a popu= lation, modelled by the linear birth and death process, is considered next. Particular attention is paid to system performance indecee which take into account the cost associated with non-zero variance and the cost of improving initial estimates of the size of the popula” tion under control.

No description available.