Determining a reliable method to detect life on another planet is an essential first step in the pursuit of discovering extraterrestrial life. Polyhydroxyalkanoates (PHAs), bioplastic polymers created by microorganisms, are strong candidates for defining the presence of extraterrestrial life due to their water insolubility, strong ultraviolet resistance, high melting points and high crystallinity, amongst other qualities. PHAs are abundant on Earth, and their chemical properties can easily be distinguished from non-biological matter. Their widespread distribution and conferred resistance to astrobiologically relevant extreme environments render PHAs highly favourable candidates for astrobiological detection. Integrating detection of PHA biosignatures into current and future life-detection instruments would be useful for the planetary search for life. PHAs are analysed and characterized in laboratories by gas chromatography-mass spectrometry, infrared spectroscopy, Raman spectroscopy and immunoassay analysis in addition to other methods. We outline a path forward to integrate PHA detection in astrobiology missions to aid the search for extraterrestrial life.

Cognitive consequences of hormonal contraceptives (HCs) are largely underexplored, despite the popularity of use. This study investigates the association between perseverance during cognitively challenging tasks and the use of HCs among Danish women. We hypothesised that women using HCs show decreased perseverance across tasks compared to their naturally cycling counterparts. We further hypothesised that HC using women would show decreased performance as a measure of accuracy (i.e. more incorrect answers) compared to naturally cycling women. The study used a cross-sectional repeated measures design, consisting of a Danish version of the Anagram Persistence Task and the Hagen Matrices Test, followed by an extensive survey documenting menstrual and HC history for each participant. The study was conducted online. Data processing was conducted on data from 129 participants. The former hypothesis was analysed through multilevel regression with a nested random effects structure on log-transformed data. The latter hypothesis was analysed through a multilevel generalised linear model with a nested random effects structure using the binomial family. No support was found for either of the hypotheses.

The overlap between virtue epistemology and the philosophy of education has been dominated by discussions of the epistemic qualities of good learners, that is, the intellectual virtues that must be nurtured in students. Not much has been said about the epistemic qualities of good teachers expressed in virtue-theoretic terms. This paper offers a preliminary account of such qualities, which are designated as pedagogical virtues. I use Battaly's pluralist conception of intellectual virtue as a starting point, then describe a pedagogical virtue as an intellectual virtue with an other-regarding success or motivational component. I end with an elucidation of the pedagogical versions of two mainstream intellectual virtues, perseverance and inquisitiveness.

The fourth age remains a poorly understood phenomenon and there is a lack of understanding of the perceptions of those who might be considered to be living in it. This article draws on findings from a study of dignity in later life which examined the day-to-day experiences of participants who were in need of support and care because of failing health. It discusses their accounts of the changes to their sense of self and their identity that came about as a result of their ageing and health problems and looks also at the ways in which the support and care they received helped to shape their adjustment to those changes. The accounts given by participants reveal a great deal about the physical, mental and emotional effort entailed in maintaining a sense of self and highlight the essential role played by social relationships in the maintenance of identity. These findings are analysed by reference to emerging theories of the fourth age.