Microbial Similarity between Students in a Common Dormitory Environment Reveals the Forensic Potential of Individual Microbial Signatures.

The microbiota of the built environment is an amalgamation of both human and environmental sources. While human sources have been examined within single-family households or in public environments, it is unclear what effect a large number of cohabitating people have on the microbial communities of their shared environment. We sampled the public and private spaces of a college dormitory, disentangling individual microbial signatures and their impact on the microbiota of common spaces. We compared multiple methods for marker gene sequence clustering and found that minimum entropy decomposition (MED) was best able to distinguish between the microbial signatures of different individuals and was able to uncover more discriminative taxa across all taxonomic groups. Further, weighted UniFrac- and random forest-based graph analyses uncovered two distinct spheres of hand- or shoe-associated samples. Using graph-based clustering, we identified spheres of interaction and found that connection between these clusters was enriched for hands, implicating them as a primary means of transmission. In contrast, shoe-associated samples were found to be freely interacting, with individual shoes more connected to each other than to the floors they interact with. Individual interactions were highly dynamic, with groups of samples originating from individuals clustering freely with samples from other individuals, while all floor and shoe samples consistently clustered together.IMPORTANCE Humans leave behind a microbial trail, regardless of intention. This may allow for the identification of individuals based on the "microbial signatures" they shed in built environments. In a shared living environment, these trails intersect, and through interaction with common surfaces may become homogenized, potentially confounding our ability to link individuals to their associated microbiota. We sought to understand the factors that influence the mixing of individual signatures and how best to process sequencing data to best tease apart these signatures

Poor choice? Smith, Hayek and the moral economy of food consumption

This paper explores the moral economy of food in the United Kingdom via discourses on food bank usage and obesity. It argues that both of these markers of malnutrition were interpreted under the Conservative-led governments of David Cameron (2010–2016) as failings of personal responsibility and identified primarily with the working class, advancing the assumption that poor people make poor choices. Based on a critique of this account, our wider contribution is two-fold. First, we identify the Hayekian lineage of the discourse of personal responsibility, highlighting its utility in facilitating a form of neoliberal market consent through its insistence on self-reliance. Second, we stake out an alternative to this conceptualization through a discussion of Adam Smith’s notion of self-command, which we call interpersonal responsibility

Once Upon a Time

This paper is a short reflection on exposing myself to a variety of different media, (books, comic books, and television shows), that contains concepts on time travel. With this exposure, I will then attempt to draw my own comic book with time travel in it

Online Tribes and Digital Authority:What Can Social Theory Bring to Digital Archaeology?

From early discussions of the disruptive potential of computer technologies for archaeological applications, to the present era of digital archaeology as the technical underpinning of modern archaeological practice, we have continued to debate the potential impacts of digital communication and digital capture and storage on our knowledge, profession and communications. The increased use of digital tools and methods for archaeological research and dissemination, as well as what Roosevelt (2015) has referred to as the shift to the digital paradigm within archaeological practice, leads us to suggest that the impact of this paradigm shift requires careful and critical examination. This article will examine the edges of the disciplines of archaeology and sociology, where we aim to advance our understanding of the relationship between digital technologies and archaeological knowledge from a uniquely social perspective, using the theoretical approaches of both classic and modern sociologists. The application of this lens of sociology to digital archaeology equips us to understand how archaeology and archaeological practice is situated in a social world, which is especially relevant in the Global West, where digital technology is ubiquitous. Through a critical consideration of the complexity of use of digital technologies within digital archaeology, we can begin to shift our focus away from the character and method of tools and workflow, to the background of intellectual power and influence

Resolution of Key Roles for the Distal Pocket Histidine in Cytochrome c Nitrite Reductases

Cytochrome c nitrite reductases perform a key step in the biogeochemical N-cycle by catalyzing the six-electron reduction of nitrite to ammonium. These multi-heme cytochromes contain a number of His/His ligated c-hemes for electron transfer and a structurally differentiated heme that provides the catalytic center. The catalytic heme has proximal ligation from lysine, or histidine, and an exchangeable distal ligand bound within a pocket that includes a conserved histidine. Here we describe properties of a penta-heme cytochrome c nitrite reductase in which the distal His has been substituted by Asn. The variant is unable to catalyze nitrite reduction despite retaining the ability to reduce a proposed intermediate in that process, namely, hydroxylamine. A combination of electrochemical, structural and spectroscopic studies reveals that the variant enzyme simultaneously binds nitrite and electrons at the catalytic heme. As a consequence the distal His is proposed to play a key role in orienting the nitrite for N-O bond cleavage. The electrochemical experiments also reveal that the distal His facilitates rapid nitrite binding to the catalytic heme of the native enzyme. Finally it is noted that the thermodynamic descriptions of nitrite- and electron-binding to the active site of the variant enzyme are modulated by the prevailing oxidation states of the His/His ligated hemes. This is behavior that is likely to be displayed by other multi-centered redox enzymes such that there are wide implications for considering the determinants of catalytic activity in this important and varied group of oxidoreductases

Understanding substrate substituent effects to improve catalytic efficiency in the SABRE hyperpolarisation process

The use of parahydrogen based hyperpolarisation in NMR is becoming more widespread due to the rapidly expanding range of target molecules and low-cost of parahydrogen production. Hyperpolarisation via SABRE catalysis employs a metal complex to transfer polarisation from parahydrogen into a substrate whilst they are bound. In this paper we present a quantitative study of substrate–iridium ligation effects by reference to the substrates 4-chloropyridine (A), 4-pyridinecarboxaldehyde methyl hemiacetal (B), 4-methylpyridine (C) and 4-methoxypyridine (D), and evaluate the role they play in the SABRE catalysis. Substrates whose substituents enable stronger associations yield slower substrate dissociation rates (kd). A series of variable temperature studies link these exchange rates to optimal SABRE performance and reveal the critical impact of NMR relaxation times (T1). Longer catalyst residence times are shown to result in shorter substrate T1 values in solution as binding to iridium promotes relaxation thereby not only reducing SABRE efficiency but decreasing the overall level of achieved hyperpolarisation. Based on these data, a route to achieve more optimal SABRE performance is defined

PropBase “Warehouse” architecture

PropBase is a “data warehouse” system that extracts, transforms and loads data into a simplified data model from across BGS’s heterogeneous property data sources into a single view so that the data is compatible and accessible from a single interface. The system consists of: data tables that form the core of a simplified data structure; coding routines that are run at regular intervals for the extraction, transformation and load of data into the simplified data structures, a second tier partitioned denormalized data access layer that serves as the data access point by applications. The system also includes a suite of java coded search utilities that facilitate easy data discovery and download to allow for the complex synthesis of many data types simultaneously. ; There is also a web service to allow for machine‐to‐machine interaction, enabling other software systems to directly interrogate the datasets to visualise and manipulate them. This system will have a significant impact by allowing multiple datasets to be rapidly integrated for scientific understanding whilst ensuring that data is properly managed and available for future use

Experimentally increased brood size accelerates actuarial senescence and increases subsequent reproductive effort in a wild bird population

The assumption that reproductive effort decreases somatic state, accelerating ageing, is central to our understanding of life‐history variation. Maximal reproductive effort early in life is predicted to be maladaptive by accelerating ageing disproportionally, decreasing fitness. Optimality theory predicts that reproductive effort is restrained early in life to balance the fitness contribution of reproduction against the survival cost induced by the reproductive effort. When adaptive, the level of reproductive restraint is predicted to be inversely linked to the remaining life expectancy, potentially resulting in a terminal effort in the last period of reproduction. Experimental tests of the reproductive restraint hypothesis require manipulation of somatic state and subsequent investigation of reproductive effort and residual life span. To our knowledge the available evidence remains inconclusive, and hence reproductive restraint remains to be demonstrated. We modulated somatic state through a lifelong brood size manipulation in wild jackdaws and measured its consequences for age‐dependent mortality and reproductive success. The assumption that lifelong increased brood size reduced somatic state was supported: Birds rearing enlarged broods showed subsequent increased rate of actuarial senescence, resulting in reduced residual life span. The treatment induced a reproductive response in later seasons: Egg volume and nestling survival were higher in subsequent seasons in the increased versus reduced broods' treatment group. We detected these increases in egg volume and nestling survival despite the expectation that in the absence of a change in reproductive effort, the reduced somatic state indicated by the increased mortality rate would result in lower reproductive output. This leads us to conclude that the higher reproductive success we observed was the result of higher reproductive effort. Our findings show that reproductive effort negatively covaries with remaining life expectancy, supporting optimality theory and confirming reproductive restraint as a key factor underpinning life‐history variation