A temperate river estuary is a sink for methanotrophs adapted to extremes of pH, temperature and salinity

River Tyne (UK) estuarine sediments harbour a genetically and functionally diverse community of methane-oxidizing bacteria (methanotrophs), the composition and activity of which were directly influenced by imposed environmental conditions (pH, salinity, temperature) that extended far beyond those found in situ. In aerobic sediment slurries methane oxidation rates were monitored together with the diversity of a functional gene marker for methanotrophs (pmoA). Under near in situ conditions (4-30°C, pH 6-8, 1-15gl-1 NaCl), communities were enriched by sequences affiliated with Methylobacter and Methylomonas spp. and specifically a Methylobacter psychrophilus-related species at 4-21°C. More extreme conditions, namely high temperatures ≥40°C, high ≥9 and low ≤5 pH, and high salinities ≥35gl-1 selected for putative thermophiles (Methylocaldum), acidophiles (Methylosoma) and haloalkaliphiles (Methylomicrobium). The presence of these extreme methanotrophs (unlikely to be part of the active community in situ) indicates passive dispersal from surrounding environments into the estuary

Private Revenge and its Relation to Punishment

In contrast to the vast literature on retributive theories of punishment, discussions of private revenge are rare in moral philosophy. This paper reviews some examples, from both classical and recent writers. It detects, both in the philosophical tradition and in contemporary moral discourse, uncertainty and equivocation over the ethical significance of acts of revenge, and in particular over their possible resemblances, in motive, purpose or justification, to acts of lawful punishment. A key problem for the coherence of our ethical conception of revenge, it suggests, is the consideration that certain acts of revenge may be just (at least in the minimal sense that the victim of revenge has no grounds for complaint against the revenger) and yet be generally agreed to be morally wrong. It argues that the challenge of explaining adequately why private revenge is morally wrong poses particular difficulty for purely retributive theories of punishment, since without invoking consequentialist reasons it does not seem possible adequately to motivate an objection to just and proportionate acts of revenge. The paper concludes by identifying some of the directions in which further reflection on the moral and political significance of revenge might proceed

Personal Identity and Practical Reason: The Failure of Kantian Replies to Parfit

ABSTRACT: This essay examines and criticizes a set of Kantian objections to Parfit's attempt in Reasons and Persons to connect his theory of personal identity to practical rationality and moral philosophy. Several of Parfit's critics have tried to sever the link he forges between his metaphysical and practical conclusions by invoking the Kantian thought that even if we accept his metaphysical theory of personal identity, we still have good practical grounds for rejecting that theory when deliberating about what to do. The argument between Parfit and his opponents illuminates broader questions about the relationship between our metaphysical beliefs and ourpractical reasons.RÉSUMÉ: Cet article examine et critique un ensemble d'objections kantiennes à la tentative de Parfit, dans Reasons and Persons, d'ajuster sa théorie de l'identité personnelle à la rationalité pratique et à la philosophie morale. Plusieurs des critiques de Parfit ont essayé de rompre le lien qu'il tisse entre ses conclusions métaphysiques et pratiques en évoquant l'idée kantienne selon -laquelle, même si nous acceptons sa théorie métaphysique de l'identité personnelle, il existe cependant de bonnes raisons pratiques de rejeter cette théorie lorsque nous délibérons à propos de ce que nous devons faire. Le débat entre Parfit et ses adversaires nous éclaire sur un questionnement plus large à propos du rapport entre croyance métaphysique et raison pratique

Procedural justice and the problem of intellectual deference

It is a well-established fact that we tend to underestimate our susceptibility to cognitive bias on account of overconfidence, and thereby often fail to listen to intellectual advice aimed at reducing such bias. This is the problem of intellectual deference. The present paper considers this problem in contexts where educators attempt to teach students how to avoid bias for purposes of instilling epistemic virtues. It is argued that recent research in social psychology suggests that we can come to terms with this problem in two steps, the second of which involves educators communicating their intellectual advice in a procedurally just manner. The components of the relevant form of procedural justice are specified and related to Miranda Fricker and David Coady?s notions of epistemic justice. Finally, a series of objections are considered and responded to

Interpersonal comparisons of the good : epistemic not impossible

To evaluate the overall good/welfare of any action, policy or institutional choice we need some way of comparing the benefits and losses to those affected: we need to make interpersonal comparisons of the good/welfare. Yet sceptics have worried either: (1) that such comparisons are impossible as they involve an impossible introspection across individuals, getting ‘into their minds’; (2) that they are indeterminate as individual-level information is compatible with a range of welfare numbers; or (3) that they are metaphysically mysterious as they assume the existence either of a social mind or of absolute levels of welfare when no such things exist. This article argues that such scepticism can potentially be addressed if we view the problem of interpersonal comparisons as fundamentally an epistemic problem – that is, as a problem of forming justified beliefs about the overall good based on evidence of the individual good

The bacteriohopanepolyol inventory of novel aerobic methane oxidising bacteria reveals new biomarker signatures of aerobic methanotrophy in marine systems

Aerobic methane oxidation (AMO) is one of the primary biologic pathways regulating the amount of methane (CH4) released into the environment. AMO acts as a sink of CH4, converting it into carbon dioxide before it reaches the atmosphere. It is of interest for (paleo)climate and carbon cycling studies to identify lipid biomarkers that can be used to trace AMO events, especially at times when the role of methane in the carbon cycle was more pronounced than today. AMO bacteria are known to synthesise bacteriohopanepolyol (BHP) lipids. Preliminary evidence pointed towards 35-aminobacteriohopane-30,31,32,33,34-pentol (aminopentol) being a characteristic biomarker for Type I methanotrophs. Here, the BHP compositions were examined for species of the recently described novel Type I methanotroph bacterial genera Methylomarinum and Methylomarinovum, as well as for a novel species of a Type I Methylomicrobium. Aminopentol was the most abundant BHP only in Methylomarinovum caldicuralii, while Methylomicrobium did not produce aminopentol at all. In addition to the expected regular aminotriol and aminotetrol BHPs, novel structures tentatively identified as methylcarbamate lipids related to C-35 amino-BHPs (MCBHPs) were found to be synthesised in significant amounts by some AMO cultures. Subsequently, sediments and authigenic carbonates from methane-influenced marine environments were analysed. Most samples also did not contain significant amounts of aminopentol, indicating that aminopentol is not a useful biomarker for marine aerobic methanotophic bacteria. However, the BHP composition of the marine samples do point toward the novel MC-BHPs components being potential new biomarkers for AMO

Against the bifurcation of virtue

It has become customary in the virtue epistemological literature to distinguish between responsibilist and reliabilist virtue theories. More recently, certain problems affecting the former have prompted epistemologists to suggest that this distinction in virtue theory maps on to a distinction in virtue, specifically between character and faculty virtue. I argue that we lack good reason to bifurcate virtue in this manner, and that this moreover counts in favor of the virtue reliabilist

Magnetoelectric ordering of BiFeO3 from the perspective of crystal chemistry

In this paper we examine the role of crystal chemistry factors in creating conditions for formation of magnetoelectric ordering in BiFeO3. It is generally accepted that the main reason of the ferroelectric distortion in BiFeO3 is concerned with a stereochemical activity of the Bi lone pair. However, the lone pair is stereochemically active in the paraelectric orthorhombic beta-phase as well. We demonstrate that a crucial role in emerging of phase transitions of the metal-insulator, paraelectric-ferroelectric and magnetic disorder-order types belongs to the change of the degree of the lone pair stereochemical activity - its consecutive increase with the temperature decrease. Using the structural data, we calculated the sign and strength of magnetic couplings in BiFeO3 in the range from 945 C down to 25 C and found the couplings, which undergo the antiferromagnetic-ferromagnetic transition with the temperature decrease and give rise to the antiferromagnetic ordering and its delay in regard to temperature, as compared to the ferroelectric ordering. We discuss the reasons of emerging of the spatially modulated spin structure and its suppression by doping with La3+.Comment: 18 pages, 5 figures, 3 table