Contraceptive use and fertility transitions: The distinctive experience of sub-Saharan Africa

Background: Continued rapid population growth in sub-Saharan Africa is driven predominantly by high fertility. Contraceptive use was a key determinant of past fertility transitions. An analysis of this relationship in sub-Saharan Africa can yield a better understanding of the region's prospects for fertility decline. Methods: Using global estimates and projections, we describe trends in contraceptive use and fertility and analyse the relationship between the two. Timing, pace, and level parameters derived from Bayesian hierarchical models of historic contraceptive and fertility transitions are used to investigate how the experience of sub-Saharan Africa may be distinctive. Results: Fertility in sub-Saharan Africa fell from 6.4 births per woman in 1990 to 4.6 in 2020, the highest among regions today. Contraceptive use among married/in-union women in sub-Saharan Africa increased from 13Š to 33Š over the same period, and remains the region with lowest use. At all levels of contraceptive use, countries of sub-Saharan Africa tend towards higher fertility compared to other regions. Transitions in contraceptive use and fertility have occurred later in sub-Saharan Africa, and have been slower in Middle and Western Africa (but not Eastern and Southern Africa), compared to the experience of Asia, Latin America, and the Caribbean. Contribution: Based on an analysis using Bayesian models, we demonstrate large differences across countries in the pace and timing of fertility and contraceptive use transitions, and we confirm that Middle and Western Africa are distinct. The findings from these separate and independent models are similar, lending additional support to the validity of these conclusions

Impact of internal migration on population redistribution in Europe: Urbanisation, counterurbanisation or spatial equilibrium?

The classical foundations of migration research date from the 1880s with Ravenstein’s “Laws of migration”, which represent the first comparative analyses of internal migration. While his observations remain largely valid, the ensuing century has seen considerable progress in data collection practices and methods of analysis, which in turn has permitted theoretical advances in understanding the role of migration in population redistribution. Coupling the extensive range of migration data now available with these recent theoretical and methodological advances, we endeavour to advance beyond Ravenstein’s understanding by examining the direction of population redistribution and comparing the impact of internal migration on patterns of human settlement in 27 European countries. Results show that the overall redistributive impact of internal migration is low in most European countries but the mechanisms differ across the continent. In Southern and Eastern Europe migration effectiveness is above average but is offset by low migration intensities, whereas in Northern and Western Europe high intensities are absorbed in reciprocal flows resulting in low migration effectiveness. About half the European countries are experiencing a process of concentration toward urbanised regions, particularly in Northern, Central and Eastern Europe, whereas countries in the West and South are undergoing a process of population deconcentration. These results suggest that population deconcentration is now more common than it was in the 1990s when counterurbanisation was limited to Western Europe. The results show that 130 years on, Ravenstein’s law of migration streams and counter-streams remains a central facet of migration dynamics, while underlining the importance of simple yet robust indices for the spatial analysis of migration

USP9X stabilizes XIAP to regulate mitotic cell death and chemoresistance in aggressive B-cell lymphoma

The mitotic spindle assembly checkpoint (SAC) maintains genome stability and marks an important target for antineoplastic therapies. However, it has remained unclear how cells execute cell fate decisions under conditions of SAC‐induced mitotic arrest. Here, we identify USP9X as the mitotic deubiquitinase of the X‐linked inhibitor of apoptosis protein (XIAP) and demonstrate that deubiquitylation and stabilization of XIAP by USP9X lead to increased resistance toward mitotic spindle poisons. We find that primary human aggressive B‐cell lymphoma samples exhibit high USP9X expression that correlate with XIAP overexpression. We show that high USP9X/XIAP expression is associated with shorter event‐free survival in patients treated with spindle poison‐containing chemotherapy. Accordingly, aggressive B‐cell lymphoma lines with USP9X and associated XIAP overexpression exhibit increased chemoresistance, reversed by specific inhibition of either USP9X or XIAP. Moreover, knockdown of USP9X or XIAP significantly delays lymphoma development and increases sensitivity to spindle poisons in a murine Eμ‐Myc lymphoma model. Together, we specify the USP9X–XIAP axis as a regulator of the mitotic cell fate decision and propose that USP9X and XIAP are potential prognostic biomarkers and therapeutic targets in aggressive B‐cell lymphoma

Abstracts from the 8th International Conference on cGMP Generators, Effectors and Therapeutic Implications

This work was supported by a restricted research grant of Bayer AG

Estimating historical total fertility rates for Australia and its states

Australian Bureau of Statistics Total Fertility Rate (TFR) statistics are available from 1921 for Australia, and for census years between 1947 and 1966 for the states, and then on an annual basis from 1971. Using historical, statistical publications, annual TFRs for Australia and the states dating back to federation in 1901 were calculated directly in years where data are available and estimated indirectly via the standardized fertility ratio in other years. For some periods where direct TFR estimation was applied, age-specific births used in the numerators of fertility rates must be estimated from partial data. Combined with Australian Bureau of Statistics data, the authors estimated TFRs contribute an uninterrupted time series of national and state TFRs for Australia from 1901 to 2011

Spatially consistent local area population estimates for Australia, 1986-2011

In 2011 the Australian Bureau of Statistics (ABS) introduced a radical new statistical geography for Australia. It then prepared a time series of Estimated Resident Populations (ERPs) by age and sex at the local scale (termed SA2 areas) back to 2001 on the new boundaries. However, a longer time series would be valuable to researchers. The aim of the work reported here was to extend the SA2 area ERPs back to 1986. A combination of small area census counts, official ERPs, look-up tables linking different statistical geographies, one-dimensional scaling, and iterative proportional fitting were employed to produce population estimates for SA2 areas of the new statistical geography. Population estimates for census years 1986, 1991 and 1996 by sex and 5 year age group were produced for SA2 areas. In combination with the official ABS ERPs for 2001, 2006 and 2011, these constitute a data set of spatially-consistent local area population estimates covering a 25 year period. The data are available in an Excel workbook accompanying this paper

Differences in attitudes towards immigration between Australia and Germany: the role of immigration policy

"This paper investigates the connection between national immigration policy and a society's attitudes towards immigration. It argues that a country's immigration policy framework plays an important role in the formation of attitudes towards immigration by shaping the local national context of the receiving country. It examines the influence of a country's immigration policy framework by contrasting two countries - Australia and Germany - that developed remarkably different immigration policies in response to large immigration movements during the post-war period. We explore attitudes towards immigration on four dimensions: (1) the national economy, (2) the labour market, (3) the national culture, and (4) the level of immigrant influx. The analyses reveal three main findings. First, people in Australia tend to display more positive attitudes towards immigration than in Germany. Second, in both countries, attitudes towards immigration tend to be influenced in a similar way by an individual's socio-economic background and feelings of national identity (in the form of nationalism and patriotism). Third, immigration policy represents a strong indicator of attitudes towards immigration. We found that the planned integrative immigration policy in Australia supports the formation of more positive attitudes towards immigration by influencing people's perception on the economic and socio-cultural impacts of immigration." (author's abstract

Global trends in internal migration

This chapter sets the case-study countries of Chapters 5-11 in a wider context. It does so by presenting evidence on migration levels and trends for a wider range of countries across the world using data prepared by the IMAGE project. It focusses primarily on the first decade of the twenty-first century but draws on earlier data where it is available. It finds that North America and Oceania have the highest migration intensities but that the picture in Europe is mixed. Countries with the highest levels of income tend to have the highest intensities. Declining migration intensities appear to be universal across North America and Oceania, but they are also common in Latin America and, Asia, and even in Africa. They are therefore not confined to just high-income countries. There is no evidence to suggest that falling intensities are just a product of advanced economic development

Australia: the long-run decline in internal migration intensities

Lying towards the top of the international scale in migration intensity, Australia has seen migration rates fall across all spatial scales since the 1970s. The chapter starts by discussing the data that are available to study migration and the adjustments made to allow long-term comparisons using consistent geographies. It then explores temporal and geographical trends before considering the impact of changes in age structure on migration rates. The chapter finds that short-distance moves started to decline in the early 1980s and inter-state migration since the 1990s. Latterly, the sharpest declines have been for long-distance moves. There is less population redistribution between different types of area. It is concluded that the ageing of the population accounted for about 20% of the fall but that migration was being delayed as young adults delayed key life events. Other factors suggested as explaining the decline included decreasing housing availability and affordability and greater evenness and stability in the Australian space economy, slowing GDP growth during and after the Great Recession is argued to have also reduced migration