Robustness of Mammalian Gut Microbiota to Humanization in Captivity

In mammals, the composition of the gut microbiota is associated with host phylogenetic history, and host-lineage specific microbiota have been shown, in some cases, to contribute to fitness-related traits of their hosts. However, in primates, captivity can disrupt the native microbiota through a process of humanization in which captive hosts acquire gut microbiota constituents found in humans. Despite the potential importance of this process for the health of captive hosts, the degree to which captivity humanizes the gut microbiota of other mammalian taxa has not been explored. Here, we analyzed hundreds of published gut microbiota profiles generated from wild and captive hosts spanning seven mammalian families to investigate the extent of humanization of the gut microbiota in captivity across the mammalian phylogeny. Comparisons of these hosts revealed compositional convergence between captive mammal and human gut microbiota in the majority of mammalian families examined. This convergence was driven by a diversity of microbial lineages, including members of the Archaea, Clostridium, and Bacteroides. However, the gut microbiota of two families—Giraffidae and Bovidae—were remarkably robust to humanization in captivity, showing no evidence of gut microbiota acquisition from humans relative to their wild confamiliars. These results demonstrate that humanization of the gut microbiota is widespread in captive mammals, but that certain mammalian lineages are resistant to colonization by human-associated gut bacteria.

The region and its resources

This chapter describes the landscapes of production found around London. Salterns and stone quarries in the Thames estuary, managed woodlands upriver of the city, and the ironworking sites of the High Weald are considered, along with the evidence for livestock and arable farming. These extraction industries responded to the creation of the Roman city, and saw considerable intensification from the Flavian period into the second century. This drew on the development of a supporting infrastructure that benefitted from military engineering and management, and is argued to have responded to elevated procuratorial demand. Some surplus may have been raised by taxes and rents in kind, and parallels are drawn with sharecropping arrangements for tenant farming documented in North Africa. The potential importance of imperial and other estates is also reviewed. Whilst direct evidence is lacking it is argued that imperial land-holdings would have been extensive in conquered territories, and this may account for some of the particularities of the economic relationship between London and its hinterland.

Antonine contraction (c. AD 165–80)

London appears to have shrunk significantly in the Antonine period, although the evidence remains contested. A major concern has been expressed over whether bioturbation and disturbance has removed the evidence of slightly built timber structures, leaving us with an exaggerated idea of the scale of contraction. This chapter looks to the detail of this evidence, including the formation of a dark-earth horizon that may mark the conversion of abandoned buildings to urban wastelands, to conclude that 57 per cent of sites show evidence of contraction that cannot be accounted for by later disturbance. It is consequently estimated that London’s population may have reduced from over 30,000 to under 20,000. Depopulation was perhaps hastened by an evacuation of the military garrison from the Cripplegate fort, and is reflected in reduced settlement densities in London’s rural hinterland and the cessation of some industrial production. There were no signs of this contraction before c. AD 165, but little evidence of routine urban maintenance in the following decades. Factors that might have contributed to London’s depopulation are considered. One of the most important may have been urban flight and manpower shortages following the epidemic known as the plague of Galens. Anxiety over the effects of this plague is attested by an amulet inscribed with a magical phylactery from the Thames foreshore, and the popularity of a London cult of Apollo the archer. The potential importance of such a pandemic to the changed mentalities of later antiquity is considered.

Bridging the Gap Between Science and Practice: Research Collaboration and the Perception of Research Findings

Research collaboration promises a useful approach to bridging the gap between research and practice and thus promoting evidence-informed education. This study examines whether information on research collaboration can influence the reception of research knowledge. We assume that the composition of experts from the field and scientists in a research team sends out signals that influence trust in as well as the relevance and applicability of the finding. In a survey experiment with practitioners from the field of adult education the influence of different research team compositions around an identical finding is tested. The results show overall high trust, relevance and applicability ratings with regard to the finding, regardless of the composition of the research team. We discuss the potential importance of additional information about research collaborations for effective knowledge translation and point out the need for more empirical research.

Simple and Two-Level Hierarchical Bayesian Approaches for Parameter Estimation with One- and Two-Layer Evapotranspiration Models of Crop Fields

The two-layer Shuttleworth–Wallace (SW) evapotranspiration (ET) model has been widely used for predicting ET with good results. Since the SW model has a large number of specific parameters, these parameters have been estimated using a simple non-hierarchical Bayesian (SB) approach. To further improve the performance of the SW model, we aimed to assess parameter estimation using a two-level hierarchical Bayesian (HB) approach that takes into account the variation in observed conditions through the comparison with a traditional one-layer Penman–Monteith (PM) model. The difference between the SB and HB approaches were evaluated using a field-based ET dataset collected from five agricultural fields over three seasons in Myanmar. For a calibration period with large variation in environmental factors, the models with parameters calibrated by the HB approach showed better fitting to observed ET than that with parameters estimated using the SB approach, indicating the potential importance of accounting for seasonal fluctuations and variation in crop growth stages. The validation of parameter estimation showed that the ET estimation of the SW model with calibrated parameters was superior to that of the PM model, and the SW model provided acceptable estimations of ET, with little difference between the SB and HB approaches.

Autosuggestion: a cognitive process that empowers your brain?

Autosuggestion is a cognitive process that is believed to enable control over one’s own cognitive and physiological states. Despite its potential importance for basic science and clinical applications, such as in rehabilitation, stress reduction, or pain therapy, the neurocognitive mechanisms and psychological concepts that underlie autosuggestion are poorly defined. Here, by reviewing empirical data on autosuggestion and related phenomena such as mental imagery, mental simulation, and suggestion, we offer a neurocognitive concept of autosuggestion. We argue that autosuggestion is characterized by three major factors: reinstantiation, reiteration, and volitional, active control over one’s own physiological states. We also propose that autosuggestion might involve the ‘overwriting’ of existing predictions or brain states that expect the most common (but not desired) outcome. We discuss potential experimental paradigms that could be used to study autosuggestion in the future, and discuss the strengths and weaknesses of current evidence. This review provides a first overview on how to define, experimentally induce, and study autosuggestion, which may facilitate its use in basic science and clinical practice.