Modelling the age pattern of fertility: an individual-level approach.

Fitting statistical models to aggregate data is still the dominant approach in many demographic and biodemographic applications. Although these macro-level models have proven useful for a variety of tasks, they often have no demographic interpretation. Individual-level modelling, on the other hand, offers a deeper understanding of the mechanisms underlying observed patterns.

Ageing as a two-phase process: theoretical framework.

Human ageing, along with the ageing of conventional model organisms, is depicted as a continuous and progressive decline of biological capabilities accompanied by an exponentially increasing mortality risk. However, not all organisms experience ageing identically and our understanding of the phenomenon is coloured by human-centric views. Ageing is multifaceted and influences a diverse range of species in varying ways.

Smurfness-based two-phase model of ageing helps deconvolve the ageing transcriptional signature.

Ageing is characterised at the molecular level by six transcriptional 'hallmarks of ageing', that are commonly described as progressively affected as time passes. By contrast, the 'Smurf' assay separates high-and-constant-mortality risk individuals from healthy, zero-mortality risk individuals, based on increased intestinal permeability. Performing whole body total RNA sequencing, we found that Smurfness distinguishes transcriptional changes associated with chronological age from those associated with biological age.

Demographic models of the reproductive process: Past, interlude, and future.

After 30 years of active development, mechanistic models of the reproductive process nearly stopped attracting scholarly interest in the early 1980s. In the following decades, fertility research continued to thrive, relying on solid descriptive work and detailed analysis of micro-level data. The absence of systematic modelling efforts, however, has also made the field more fragmented, with empirical research, theory building, and forecasting advancing along largely disconnected channels.

Socioeconomic development predicts a weaker contraceptive effect of breastfeeding.

The contraceptive effect of breastfeeding remains essential to controlling fertility in many developing regions of the world. The extent to which this negative effect of breastfeeding on ovarian activity is sensitive to ecological conditions, notably maternal energetic status, has remained controversial. We assess the relationship between breastfeeding duration and postpartum amenorrhea (the absence of menstruation following a birth) in 17 World Fertility Surveys and 284 Demographic Health Surveys conducted between 1975 and 2019 in 84 low- and middle-income countries.

[Ethical and social consequences of biomarkers that predict impending death in humans].

Fundamental research on ageing has taken an interesting turn in recent years with the rapid development of biomarkers predicting mortality in model organisms, particularly Drosophila, as well as in humans through improvements in approaches to the identification of circulating molecules in mass. These developments lead to a shift in our ability to predict the occurrence of death from the historically population level to the individual level. We question here the ethical, medical and social implications of this change of scale.

Ethical and social implications of approaching death prediction in humans - when the biology of ageing meets existential issues.

Background: The discovery of biomarkers of ageing has led to the development of predictors of impending natural death and has paved the way for personalised estimation of the risk of death in the general population. This study intends to identify the ethical resources available to approach the idea of a long-lasting dying process and consider the perspective of death prediction. The reflection on human mortality is necessary but not sufficient to face this issue.

Correction to: Fetal growth is associated with CpG methylation in the P2 promoter of the gene.

[This corrects the article DOI: 10.1186/s13148-018-0489-9.].

Fetal growth is associated with CpG methylation in the P2 promoter of the IGF1 gene.

Background: There are many reasons to think that epigenetics is a key determinant of fetal growth variability across the normal population. Since and genes are major determinants of intrauterine growth, we examined the methylation of selected CpGs located in the regulatory region of these two genes.

Methods: Cord blood was sampled in 159 newborns born to mothers prospectively followed during their pregnancy.

Impact of social inequalities at birth on the longevity of children born 1914-1916: A cohort study.

Background: Testing whether familial socioeconomic status (SES) in childhood is a predictor of mortality has rarely been done on historical cohorts.

Methods: The birth certificates of 4,805 individuals born 1914-1916 in 16 districts of the Paris region were retrieved. The handwritten information provided the occupation of parents, the legitimacy status, life events (e.

Comparison of the temperature-mortality relationship in foreign born and native born died in France between 2000 and 2009.

The daily temperature-mortality relationship is typically U shaped. The temperature of minimum mortality (MMT) has been shown to vary in space (higher at lower latitudes) and time (higher in recent periods). This indicates human populations adapt to their local environment.

Prenatal loss of father during World War One is predictive of a reduced lifespan in adulthood.

Although early-life stress is known to alter health, its long-term consequences on mortality remain largely unknown. Thanks to unique French legislation established in 1917 for war orphans and children of disabled soldiers, we were able to study the adult mortality of individuals born in 1914-1916 whose fathers were killed during World War 1. Vital information and socio-demographic characteristics were extracted manually from historical civil registers for 5,671 children born between 1 August 1914 and 31 December 1916 who were granted the status of "" (orphan of the Nation).

Space-Time Covariation of Mortality with Temperature: A Systematic Study of Deaths in France, 1968-2009.

Background: The temperature-mortality relationship has repeatedly been found, mostly in large cities, to be U/J-shaped, with higher minimum mortality temperature (MMT) at low latitudes being interpreted as indicating human adaptation to climate.

Objectives: Our aim was to partition space with a high-resolution grid to assess the temperature-mortality relationship in a territory with wide climate diversity, over a period with notable climate warming.

Methods: The 16,487,668 death certificates of persons > 65 years of age who died of natural causes in continental France (1968-2009) were analyzed.