Table of Contents

Abstract: Humans harbor distinct commensal microbiota at various anatomic sites. There has been renewed interest in the contributions of microbiota activities to human health and disease. The microbiota of the gut is the most complex of all anatomic sites in terms of total numbers of bacteria that interact closely with the mucosal immune system and contribute various functions to host physiology. Especially in the proximal large intestine a diverse microbiota ferments complex substrates such as dietary fiber and host mucins, but also metabolizes bile acids and phytoestrogens that reach the large intestine. It is now well established that microbiota composition differs between but over time also within individuals. However, a thorough understanding of the sources of variations in microbiota composition, which is an important requirement for large population based microbiota studies is lacking. Microbiota composition varies depending on what kind of sample is collected, most commonly stool samples, stool swabs or superficial rectal or intestinal biopsies, and the time of collection. Microbiota dynamics are affected by life style factors including diet and exercise that determine what nutrients reach the proximal colon and how fast these nutrients pass through (transit time). Here we review sample collection issues in gut microbiota studies and recent findings about dynamics in microbiota composition. We recommend standardizing human microbiota analysis methods to facilitate comparison and pooling between studies. Finally, we outline a need for prospective microbiota studies in large human cohorts.

Abstract: This article re-examines recent studies that link different forms of social diversity—ethnic polarization and fractionalization—to underdevelopment and an increased risk of civil war. We review theoretical arguments in favor of a connection between diversity and these social outcomes and discuss the inter-linkage between economic growth and internal conflict in situations of extreme diversity. Our analysis confirms that the relationship between ethnic polarization and civil war is ambiguous and depends on the use of civil war incidence or civil war onset as an outcome variable. Furthermore, fractionalization rather than polarization seems to be negatively related to economic growth.

Abstract: Telomeres are specialized nucleoprotein structures that have two important functions: (i) protection of the chromosomal ends from deleterious events such as chromosome fusion and degradation; (ii) counteraction of the “end replication problem” by allowing telomerase-dependent or, more rarely, telomerase-independent telomere elongation. The DNA sequences underlying these activities are short simple tandem repeats, which in vertebrate consist of a variable number of TTAGGG. Telomeres dysfunction may be caused either by the absence of telomerase activity or by mutations in telomeric proteins involved in telomere length and structure regulation. Additionally, increasing experimental evidence suggests that telomeres take part in the complex network regulating cell proliferation. Accordingly, telomeres are involved in biological process such as aging and tumor progression. In this study we determined the telomere length in two bovine Italian cattle breeds, Chianina and Maremmana, which are characterized by high longevity and range breeding. In order to account for possible variation among different tissues, we have determined telomere length in different organs such as spleen, lung and liver. Overall, the median telomere length was significant lower in Chianina (11 ± 0.69 kb) than in Maremmana (12.05 ± 1.57 kb). Moreover, telomere length variation among individuals was very low in Chianina but rather high in Maremmana. These data suggest that telomere length is influenced by the breeds. This hypothesis is confirmed by the different history of these Italian breeds. Indeed, Chianina has a long history and its size was maintained by the Breeders Association without necessity to crossbreed with other breeds, whereas the population of Maremmana underwent a dramatic shrinkage in the recent past. Therefore, breeders have crossed Maremmana with other breeds, like Charolais, and have relaxed the rules for the inclusion in the herd book.

Abstract: Public participation is a key element in nature conservation in Europe and a necessity for collecting broad scale data on biodiversity and its dynamics. However, vast societal differences exist between eastern and western European countries, resulting in problems for public participation in post-communist states as compared to western countries. Here, we compare diversity in monitoring practices and public participation in countries with different political histories. Drawing on in-depth ethnographic studies conducted in Lithuania and Poland, as well as a rapid assessment in Denmark, we have focused on the historical, cultural and social determinants of the volunteers’ participation in biodiversity monitoring. Our results indicate the reasons why volunteer involvement—as an expression of a participatory approach—has a lower incidence in the post-communist countries, compared to voluntarism common in occidental democracies. We discuss our results in the context of the main social factors considered to be a legacy of the Soviet regime.