Affective practices, care and bioscience: a study of two laboratories

Scientific knowledge-making is not just a matter of experiments, modelling and fieldwork. It also involves affective, embodied and material practices (Wetherell 2012) which can be understood together as 'matters of care' (Puig de la Bellacasa, 2011). In this paper we explore how affect spans and connects material, subjective and organisational practices, focusing in particular on the patterns of care we encountered in an observational study of two bioscience laboratories. We explore the preferred emotional subjectivities of each lab and their relation to material practice. We go on to consider flows and clots in the circulation of affect and their relation to care through an exploration of belonging and humour in the labs. We show how being a successful scientist or group of researchers involves a careful choreography of affect in relation to materials, colleagues and others to produce scientific results, subjects and workplaces. We end by considering how thinking with care troubles dominant constructions of scientific practice, successful scientific selves and collectives

Conversation with Lisa Garforth / Conversatorio con Lisa Garforth

\ua9 2023, Universidad Compultense Madrid. All rights reserved. Julia Ram\uedrez-Blanco interviews Lisa Garforth, author of the book Green Utopias and specialist in environmental utopias. With her, we talk about the possible ways of defining ecotopias, and how they manifest themselves both in literature and in different forms of social practice

Climate and failure: for a weak utopianism

Attempts to imagine a better future from within the climate emergency must work in and through failure: failing eco-social systems, failed narratives, failures of political will, failures to change consumerist lifestyles. Utopia is intimately related to failure. It is a response to something wrong or missing. As a mode of critique and creation it is definitionally impossible to realise. But the climate crisis brings distinctive dimensions, disrupting linear temporalities, resisting solutions and posing existential dilemmas. This paper works through theoretical ideas linking utopia with failure in contemporary utopian and queer theorising, adapting them to the climate context and articulating a weak utopianism in response to theorists calling for a hard or strong utopia in times of crisis. It argues that climate crisis is better understood as a world than asa problem, and explores what kinds of implicated, everyday, and entangled utopian desires might enable us to navigate the Anthropocene

A model for transition of 5 '-nuclease domain of DNA polymerase I from inert to active modes

Bacteria contain DNA polymerase I (PolI), a single polypeptide chain consisting of similar to 930 residues, possessing DNA-dependent DNA polymerase, 3'-5' proofreading and 5'-3' exonuclease (also known as flap endonuclease) activities. PolI is particularly important in the processing of Okazaki fragments generated during lagging strand replication and must ultimately produce a double-stranded substrate with a nick suitable for DNA ligase to seal. PolI's activities must be highly coordinated both temporally and spatially otherwise uncontrolled 5'-nuclease activity could attack a nick and produce extended gaps leading to potentially lethal double-strand breaks. To investigate the mechanism of how PolI efficiently produces these nicks, we present theoretical studies on the dynamics of two possible scenarios or models. In one the flap DNA substrate can transit from the polymerase active site to the 5'-nuclease active site, with the relative position of the two active sites being kept fixed; while the other is that the 5'-nuclease domain can transit from the inactive mode, with the 5'-nuclease active site distant from the cleavage site on the DNA substrate, to the active mode, where the active site and substrate cleavage site are juxtaposed. The theoretical results based on the former scenario are inconsistent with the available experimental data that indicated that the majority of 5'-nucleolytic processing events are carried out by the same PolI molecule that has just extended the upstream primer terminus. By contrast, the theoretical results on the latter model, which is constructed based on available structural studies, are consistent with the experimental data. We thus conclude that the latter model rather than the former one is reasonable to describe the cooperation of the PolI's polymerase and 5'-3' exonuclease activities. Moreover, predicted results for the latter model are presented

Executive attention, task selection and attention-based learning in a neurally controlled simulated robot

We describe the design and implementation of an integrated neural architecture, modelled on human executive attention, which is used to control both automatic (reactive) and willed action selection in a simulated robot. The model, based upon Norman and Shallice's supervisory attention system, incorporates important features of human attentional control: selection of an intended task over a more salient automatic task; priming of future tasks that are anticipated; and appropriate levels of persistence of focus of attention. Recognising that attention-based learning, mediated by the limbic system, and the hippocampus in particular, plays an important role in adaptive learning, we extend the Norman and Shallice model, introducing an intrinsic, attention-based learning mechanism that enhances the automaticity of willed actions and reduces future need for attentional effort. These enhanced features support a new level of attentional autonomy in the operation of the simulated robot. Some properties of the model are explored using lesion studies, leading to the identification of a correspondence between the behavioural pathologies of the simulated robot and those seen in human patients suffering dysfunction of executive attention. We discuss briefly the question of how executive attention may have arisen due to selective pressure

H2 production from photocatalytic reforming of PET over Pt/TiO2: The role of terephthalic acid

Photoreforming is a promising method for the conversion of waste materials with simultaneous production of H2. The use of waste polyethylene terephthalate (PET) as a photoreforming substrate has been previously investigated, however its insolubility in aqueous media and the resistance of the aromatic terephthalate towards conversion are major obstacles. Commonly an alkaline pretreatment step is used to initiate hydrolysis to ethylene glycol and terephthalic acid which promotes H2 evolution. However, in this work we have found that TPA has both promotional and inhibitory effects by modification of the catalyst surface that depend on the relative concentration of ethylene glycol. Terephthalic acid inhibits the oxidation reactions by scavenging hydroxyl radicals and blocking complexation sites. This leads to lower H2 evolution compared to the photoreforming of an equivalent concentration of ethylene glycol. Even in trace amounts, terephthalic acid would still inhibit the reaction unless the concentration of ethylene glycol was high enough. Surprisingly, at ethylene glycol concentrations of > 1.2 M, residual terephthalic acid promoted the reaction which is thought to be due to increasing the interaction between ethylene glycol and the catalyst surface but also an increased role of water. On the basis of these results, we suggest that, if PET is to be used as a feedstock for H2 generation by photoreforming, an initial hydrolysis should be performed after which terephthalic acid is separated for re-use. The remaining hydrolysate may then be used for photoreforming. Furthermore, the ethylene glycol concentration should be maximized in order to overcome the inhibitory effects of residual terephthalic acid

Direct observation of DNA threading in flap endonuclease complexes

Maintenance of genome integrity requires that branched nucleic acid molecules are accurately processed to produce double-helical DNA. Flap endonucleases are essential enzymes that trim such branched molecules generated by Okazaki fragment synthesis during replication. Here, we report crystal structures of bacteriophage T5 flap endonuclease in complexes with intact DNA substrates, and products, at resolutions of 1.9–2.2 Å. They reveal single-stranded DNA threading through a hole in the enzyme enclosed by an inverted Vshaped helical arch straddling the active site. Residues lining the hole induce an unusual barb-like conformation in the DNA substrate juxtaposing the scissile phosphate and essential catalytic metal ions. A series of complexes and biochemical analyses show how the substrate’s single-stranded branch approaches, threads through, and finally emerges on the far side of the enzyme. Our studies suggest that substrate recognition involves an unusual “flycasting, thread, bend and barb” mechanis

Farmers’ perceptions of climate change : identifying types

Ambitious targets to reduce greenhouse gas (GHG) emissions from agriculture have been set by both national governments and their respective livestock sectors. We hypothesize that farmer self-identity influences their assessment of climate change and their willingness to im- plement measures which address the issue. Perceptions of climate change were determined from 286 beef/sheep farmers and evaluated using principal component analysis (PCA). The analysis elicits two components which evaluate identity (productivism and environmental responsibility), and two components which evaluate behavioral capacity to adopt mitigation and adaptation measures (awareness and risk perception). Subsequent Cluster Analyses reveal four farmer types based on the PCA scores. ‘The Productivist’ and ‘The Countryside Steward’ portray low levels of awareness of climate change, but differ in their motivation to adopt pro-environmental behavior. Conversely, both ‘The Environmentalist’ and ‘The Dejected’ score higher in their awareness of the issue. In addition, ‘The Dejected’ holds a high sense of perceived risk; however, their awareness is not conflated with an explicit understanding of agricultural GHG sources. With the exception of ‘The Environmentalist’, there is an evident disconnect between perceptions of agricultural emission sources and their contribution towards GHG emissions amongst all types. If such linkages are not con- ceptualized, it is unlikely that behavioral capacities will be realized. Effective communication channels which encour- age action should target farmers based on the groupings depicted. Therefore, understanding farmer types through the constructs used in this study can facilitate effective and tai- lored policy development and implementation