Non-Gaussian buoyancy statistics in fingering convection

We examine the statistics of active scalar fluctuations in high-Rayleigh number fingering convection with high-resolution three-dimensional numerical experiments. The one-point distribution of buoyancy fluctuations is found to present significantly non-Gaussian tails. A modified theory based on an original approach by Yakhot (1989) is used to model the active scalar distributions as a function of the conditional expectation values of scalar dissipation and fluxes in the flow. Simple models for these two quantities highlight the role of blob-like coherent structures for scalar statistics in fingering convection

Sénescence, sélection sexuelle et dynamique de population du bouquetin des Alpes (Capra Ibex)

Le principal objectif de cette thèse est d’étudier les variations intra et inter individuelle pour deux traits phénotypiques reliés à la valeur sélective, et d’analyser la dynamique d’une population sauvage de bouquetin des Alpes (Capra ibex). Le premier chapitre analyse la relation de deux traits phénotypiques reliés à la valeur sélective (le gain de masse corporelle, et l’intensité d’infection parasitaire gastro-intestinal) et d’un caractère sexuel secondaire (la croissance des cornes) avec l’âge, des facteurs environnementaux, la survie, et avec l’hétérozygotie, ceci au sein d’un large échantillon de bouquetins des Alpes mâles en libertés et marqués individuellement. À travers la croissance corporelle et les comptages fécaux d’oeufs de nématodes gastro-intestinaux, il a été mis en évidence un phénomène de sénescence et de coût pour la reproduction. En analysant un large échantillon de squelettes de bouquetins mâles trouvés morts dans l’hiver pour cause de famine, nous avons trouvé que le début de la sénescence était caractérisé par la longueur de segments de croissance annuels âges spécifiques des cornes, mais pas par leur asymétrie. Enfin, des corrélations entre l’hétérozygotie et la valeur sélective ont été mises en évidence pour la croissance des cornes, mais pas pour la masse corporelle et l’intensité d’infection parasitaire. Le deuxième chapitre traite de l’importance relative de la densité dépendance et de la variabilité stochastique du climat sur la dynamique d’une population d’ongulé de montagne, à travers l’analyse de série temporelle de 45 ans de recensements de bouquetins des Alpes collectés dans le Parc National du Grand Paradis en Italie. Pendant les 28 premières années de l’étude, le nombre total de bouquetins a varié entre 2600 et 4000 sans tendance visuelle apparente. Au cours de cette période, il est apparu que des oscillations avec une périodicité de 3 à 8 ans étaient présentes. Dès 1982, les comptages de bouquetin ont augmentés régulièrement pour atteindre un pic de 5000 en 1993 et ensuite décroître. Nous avons montré que la taille de population du bouquetin était limitée à la fois par la densité dépendance et par l’épaisseur de neige. Un modèle basé sur ces deux facteurs et ajusté pour les 19 premières années de données, réussi avec succès à prédire l’augmentation et le déclin subséquent de la taille totale de la population pour les 20 dernières années de l’étude. Cette thèse conclue avec un troisième chapitre présentant deux techniques innovatrices utiles pour l’étude de populations d’ongulés en liberté.Abstract: The main objectives of this thesis are to investigate within and between-individual variation in fitness related phenotypic traits and to analyse the population dynamics of a wild population of Alpine ibex (Capra ibex). The first chapter analyzes the relationship of two fitness-related phenotypic traits (body mass gain and the intensity of gastrointestinal parasite infection) and one secondary sexual trait (horn growth) with age, environmental factors, survival and heterozygosity in a large sample of individually tagged free-ranging Alpine ibex males. Evidence for senescence and costs of reproduction in body growth and fecal counts of gastrointestinal nematode eggs was found. Analysing a large sample of male ibex skulls, found dead in winter from starvation, we found that the onset of senescence was signaled by the length of age specific yearly horn growth segments, but not by their asymmetry. Finally evidence for heterozygosity-fitness correlations was found for horn growth, but not for body mass and the intensity of parasite infection. The second chapter investigates the relative importance of density dependence and of stochastic climatic variability in the population dynamics of a mountain ungulate, analysing a 45 year long time series of Alpine ibex censuses collected in the Gran Paradiso National Park, Italy During the first 28 years of the study, the total number of ibex ranged from about 2600 to about 4000 with no visually apparent trend. During this period oscillations with periodicities of about 3 and 8 years appeared to be present. From 1982 onwards, ibex counts increased steadily and peaked at almost 5000 in 1993, decreasing afterwards. We show that the ibex population size was limited by both density dependence and deep snow. A model based on these factors fit to the first 19 years of data was successful in forecasting the increase and subsequent decline in total population size over the final 20 years of the study. The thesis concludes with a third chapter presenting two innovative techniques useful in the study of free-ranging populations of ungulates

Generation of large-scale winds in horizontally anisotropic convection

We simulate three-dimensional, horizontally periodic Rayleigh-B\'enard convection between free-slip horizontal plates, rotating about a distant horizontal axis. When both the temperature difference between the plates and the rotation rate are sufficiently large, a strong horizontal wind is generated that is perpendicular to both the rotation vector and the gravity vector. The wind is turbulent, large-scale, and vertically sheared. Horizontal anisotropy, engendered here by rotation, appears necessary for such wind generation. Most of the kinetic energy of the flow resides in the wind, and the vertical turbulent heat flux is much lower on average than when there is no wind

German Pig Farmers’ Attitudes towards Animal Welfare Programs and their Willingness to Participate in these Programs: An Empirical Study

In recent years, the image of intensive livestock production systems has been suffering from increasing public criticism. Many consumers express strong demands for higher farm animal welfare standards – especially in conventional livestock husbandry systems. This applies primarily to products from pork production, as consumers have criticized that the animals have not enough space in their stables and no possibility for outdoor access. Although pig farmers are key stakeholders for the implementation of animal welfare programs (AWPs) there is little evidence of their attitudes towards AWPs. Thus, the main objective of this investigation was to investigate pig farmers’ attitudes towards AWPs and to determine target groups for participation in AWPs. Therefore conventional pig farmers throughout Germany were questioned via an online survey. For statistical analysis an explorative factor analysis and a hierarchical cluster analysis were applied. Four factors and three farmer groups were identified which significantly differ regarding their attitudes towards AWPs and their willingness to participate in AWPs. For all groups of farmers the economic aspects are important for implementing AWPs. The orientation on the production process is strongly influenced by monetary aspects. This paper represents a starting point for the design of tailormade strategies to increase the market penetration of AWPs and to provide incentives for farmers to participate in AWPs. Further financial incentives are needed to transfer pig farmers attitudes into corresponding behaviour

German Pig Farmers’ Attitudes Towards Farm Animal Welfare And Their Willingness To Participate In Animal Welfare Pro-grams: An Empirical Study

Many consumers express strong demands for higher farm animal welfare standards – especially in conventional livestock husbandry systems. This applies primarily to products from pork production, as consumers have recognized a quality decrease in recent years. Although pig farmers are key stakeholders for the implementation of animal welfare programs (AWPs) there is little evidence of their attitudes towards farm animal welfare (FAW) and AWPs. Thus, the main objective of this investigation was to investigate pig farmers’ attitudes towards FAW and AWPs and to determine target groups for participation in AWPs. Therefore, an explorative factor analysis and a hierarchical cluster analysis were applied. Three farmer groups were identified which significantly differ regarding their attitudes towards FAW and their willingness to participate in AWPs. This paper represents a starting point for the design of tailor-made strategies to increase the market penetration of AWPs

Deregulierung in der öffentlichen Debatte in Deutschland

The study examines public statements by German politicians and economic policy advisors on questions of deregulation. The period covered stretches from the former chancellor Gerhard Schröder's speech on the Agenda 2010 reform package in early 2003 until the beginning of the financial crisis in 2007. Based on the citations found, an index is created with which one can measure the degree of support for cutting back the government's influence on the economy. According to this index, economic policy advisors have been pushing much harder for deregulation than the large majority of German politicians. Among politicians, those of the FDP have been most in favor of cutting back the government's influence, followed by the CDU/CSU politicians. Interestingly, some of the CDU/CSU politicians have been less in favor of deregulation than prominent Social Democrats.

Introduction—Up, down, round and round: Verticalities in the history of science

History of science's spatial turn has focused on the horizontal dimension, leaving the role of the vertical mostly unexplored as both a condition and object of scientific knowledge production. This special issue seeks to contribute to a burgeoning discussion on the role of verticality in modern sciences, building upon a wider interdisciplinary debate about the importance of the vertical and the volumetric in the making of modern lifeworlds. In this essay and in the contributions that follow, verticality appears as a condition of knowledge production—a set of movements and mobilities, technical challenges, political negotiations, and bodily hardships—and an object of scientific inquiry, requiring new techniques of mapping and visualisation and generative of new insights into physical processes and temporal change. By foregrounding the vertical, historians of science can gain new insights and tell new stories about how science is done in the field, the observatory, and the laboratory, and about how those sciences have helped build a modern, three‐dimensional world

Robustness of precipitation Emergent Constraints in CMIP6 models

An Emergent Constraint (EC) is a physically-explainable relationship between model simulations of a past climate variable (predictor) and projections of a future climate variable (predictand). If a significant correlation exists between the predictand and the predictor, observations of the latter can be used to constrain model projections of the former and to narrow their uncertainties. In the present study, the EC technique has been applied to the analysis of precipitation, one of the variables most affected by model uncertainties and still insufficiently analysed in the context of ECs, particularly for the recent CMIP6 model ensemble. The main challenge in determining an EC is establishing if the relationship found is physically meaningful and robust to the composition of the model ensemble. Four precipitation ECs already documented in the literature and so far tested only with CMIP3/CMIP5, three of them involving the analysis of extreme precipitation, have been reconsidered in this paper. Their existence and robustness are evaluated using different subsets of CMIP5 and CMIP6 models, verifying if the EC is still present in the most recent ensemble and assessing its sensitivity to the detailed ensemble composition. Most ECs considered do not pass this test: we found one EC not to be robust in both CMIP5 and CMIP6, other two exist and are robust in CMIP5 but not in CMIP6, and only one is verified and is robust in both model ensembles