Dynamics of hippocampal neurogenesis in adult humans.

Adult-born hippocampal neurons are important for cognitive plasticity in rodents. There is evidence for hippocampal neurogenesis in adult humans, although whether its extent is sufficient to have functional significance has been questioned. We have assessed the generation of hippocampal cells in humans by measuring the concentration of nuclear-bomb-test-derived ¹4C in genomic DNA, and we present an integrated model of the cell turnover dynamics. We found that a large subpopulation of hippocampal neurons constituting one-third of the neurons is subject to exchange. In adult humans, 700 new neurons are added in each hippocampus per day, corresponding to an annual turnover of 1.75% of the neurons within the renewing fraction, with a modest decline during aging. We conclude that neurons are generated throughout adulthood and that the rates are comparable in middle-aged humans and mice, suggesting that adult hippocampal neurogenesis may contribute to human brain function.

A horse on your plate? A cluster analysis of French consumers hippophagy acceptance.

Hippophagy is a practice that is far from being consensual, even among meat eaters. Horse meat consumption remains limited or is even strongly declining in some countries such as France. However, the nutritional, organoleptic and environmental benefits of this meat invite us to consider horse meat products as a valuable alternative source of protein. This research therefore aims to identify and characterize different profiles of consumers and non-consumers of horse meat in terms of personal values, attitudes, motivations and behaviors. Based on data from a quantitative survey among 482 French meat consumers, we distinguish 4 categories of individuals: "Enthusiast", "Distant", "Aversive" and "Potential". While "Distant" and "Aversive" show a low level of acceptability towards horse meat, "Enthusiast" and "Potential" reveal characteristics that are favorable to horse meat consumption. Targeted strategies to support the horse meat market are proposed and discussed in light of these results that also provide insight into the future for meat in general.

Horsemeat consumption in France: Determinants and sustainable market perspectives.

In France, the horsemeat market has been declining for about 50 years and has become a specialized market. Our study aims to understand this decline with regard to the drivers and practices of consumers and non-consumers of this meat, in order to estimate the potential for this market development. To study horsemeat consumption, we analyze two sets of data: two large-scale surveys carried out on the French general population, and one ad-hoc survey focusing more specifically on the representations of horses and horsemeat. Our results underline the potential for increasing horsemeat consumption from a sustainability perspective. The question of moral acceptance remains a determining factor in the consumption of this meat. Once this factor is taken into account, horsemeat appears relevant in the diversification of animal protein consumption because of its particular nutritional and environmental properties and similar culinary use to that of other red meats. Horsemeat can thus lay claim to becoming a sustainable alternative to beef consumption.

Green Assets of Equines in the European Context of the Ecological Transition of Agriculture.

Despite the decline of equine populations in the middle of the 20th century, the European horse industry is growing again thanks to economic alternatives found in the diversification of the uses of equines (sports, racing, leisure, etc.). Equines have many environmental advantages, but the fragmentation of the sector and the lack of synthetic knowledge about their environmental impacts do not enable the promotion of these assets and their effective inclusion in management practices and European policies. To highlight the equine environmental impacts, a literature review was carried out to cover the main European stakes. This work led to the identification of five "green assets", fields where equines show unique environmental advantages compared to other agricultural productions. These green assets are linked to the nature of equines (grazing and domestic biodiversity), to their geographical distribution (land use), and to their use by human beings (tourism and work). Today, when searching for sustainable solutions to modern environmental issues, the use of equines is a neglected green alternative. Better knowledge and use of equine green assets could partly respond to more ecological agricultural needs and contribute to the development of this animal industry, which has a place in regional development and in Europe's sustainable transition.

Clustering of longitudinal data by using an extended baseline: A new method for treatment efficacy clustering in longitudinal data.

Heterogeneity in treatment efficacy is a major concern in clinical trials. Clustering may help to identify the treatment responders and the non-responders. In the context of longitudinal cluster analyses, sample size and variability of the times of measurements are the main issues with the current methods. Here, we propose a new two-step method for the Clustering of Longitudinal data by using an Extended Baseline. The first step relies on a piecewise linear mixed model for repeated measurements with a treatment-time interaction. The second step clusters the random predictions and considers several parametric (model-based) and non-parametric (partitioning, ascendant hierarchical clustering) algorithms. A simulation study compares all options of the clustering of longitudinal data by using an extended baseline method with the latent-class mixed model. The clustering of longitudinal data by using an extended baseline method with the two model-based algorithms was the more robust model. The clustering of longitudinal data by using an extended baseline method with all the non-parametric algorithms failed when there were unequal variances of treatment effect between clusters or when the subgroups had unbalanced sample sizes. The latent-class mixed model failed when the between-patients slope variability is high. Two real data sets on neurodegenerative disease and on obesity illustrate the clustering of longitudinal data by using an extended baseline method and show how clustering may help to identify the marker(s) of the treatment response. The application of the clustering of longitudinal data by using an extended baseline method in exploratory analysis as the first stage before setting up stratified designs can provide a better estimation of treatment effect in future clinical trials.