Effects of stocking density on the welfare of farmed rainbow trout (Oncorhynchus mykiss)

The welfare of farmed fish is a subject of growing public, commercial and governmental interest. The Farm Animal Welfare Council’s report on the welfare of farmed fish (Anon., 1996a) highlighted stocking densities used in intensive fish production as a major welfare concern. This thesis investigates links between stocking density and welfare of rainbow trout (Oncorhynchus mykiss, Walbaum, 1972). The effects of stocking density and water quality deterioration on the welfare of rainbow trout were assessed in two controlled experiments. Fish welfare was assessed by measuring a range of morphometric (growth, fin condition), physiological (haematocrit, plasma cortisol and glucose) and immune response (lysozyme activity) indicators. Principal Components Analysis (PCA) was used to generate welfare indices based on coherence that existed between the individual welfare indicators. The first experiment stocked different numbers of fish into the tanks at the same inflow rate (60 1 min-1) to achieve stocking densities of 10, 40, and 80 kg m-3. Results suggested that, provided good water quality was maintained, stocking densities around 80 kg m-3 did not produce consistent negative effects on growth rate, stress response or immunological indicators of welfare. Fin erosion increased with increasing density, although the exact cause of the erosion remains unclear. Increased size variation and elevated cortisol levels in the 10 kg m-3 treatment, possibly linked to dominance hierarchies, indicated that low, as well as high, stocking densities may have a detrimental effect on trout welfare. The second experiment assessed the effect of water quality deterioration by adjusting inflow rate (20, 40 or 60 1 min-1) in tanks containing the same initial stocking density of fish (16 kg m-3). Inflow rate affected growth during the 3 month summer period when water temperatures were highest (≈14°C), with significantly better growth observed in the 60 1 min-1 treatment. There was no significant effect of inflow rate on cortisol, haematocrit or fin erosion, but higher mortality and poorer body condition were observed in the 20 1 min-1 treatment. A questionnaire survey of stocking density practices on UK trout farms found marked differences in the stocking practices and the perception of a high SD when comparing farms producing trout exclusively for the table market with fisheries and restocking farms. A lack of accurate flow rate data from respondents highlighted the difficulties of trying to apply alternative methods of quantifying stocking density rather than the conventional unit of kg m-3. On-farm work successfully applied the system of welfare assessment in a range of selected commercial systems and confirmed some of the findings from the tank based experiments and questionnaire survey. In summary, increased stocking density resulted in increased fin erosion although there was also the suggestion that there are welfare implications at low as well as high SD. Systems applying high SD or loading rates may run an increased risk of mass mortality in the event of system failure, necessitating the need for increased supervision and appropriate back-up systems. A universally applied SD limit will not guarantee good fish welfare and it is suggested that defining limits of key water quality parameters may prove to be more effective. Further work is required to establish thresholds of water quality parameters to safeguard fish welfare

Scientists in the MIST: Simplifying Interface Design for End Users

We are building a Malleable Interactive Software Toolkit (MIST), a tool set and infrastructure to simplify the design and construction of dynamically-reconfigurable (malleable) interactive software. Malleable software offers the end-user powerful tools to reshape their interactive environment on the fly. We aim to make the construction of such software straightforward, and to make reconfiguration of the resulting systems approachable and manageable to an educated, but non-specialist, user. To do so, we draw on a diverse body of existing research on alternative approaches to user interface (UI) and interactive software construction, including declarative UI languages, constraint-based programming and UI management, reflection and data-driven programming, and visual programming techniques

Social Media and Leibniz’ Monadology Artificial Experience I

The Yale-Düsseldorf Working Group on Philosophy and Media juxtaposes thought figures from the history of philosophy with concrete media-technical ensembles under the rubric ‘Artificial Experience’. More specifically, it studies the artificiality of human and non-human experience as media. The hypothesis is that historical philosophical figures offer different perspectives on traditional as well as current media-technical objects. Following Gilbert Simondon’s theory, the group also hopes to uncover specific modes of experience embedded in certain media-technical ensembles, modes which have remained hidden because the better thought figure has not yet been tested. This workshop will juxtapose Leibniz’s ‘monad’ — understood as an atomistic and highly perspectival account of experience — with current media technologies (for example, social media). The workshop is divided into two sessions. The first is a collaborative, in-depth reading of the Monadology and related texts and letters, asking questions such as: what forms of human and non-human experience can be observed there? Can this be understood as a mode of media or artificial experience? What roles do historical media play in Leibniz, the window, the mirror, the city, etc.? The second session will connect the figure of the monad with concrete media technologies proposed by participants themselves. What dimension of experience can be brought to light in the chosen media technology, if it is linked with Leibniz’s monadic thinking? Two further workshops organized by Martin Doll and Paul North on thought figures from Kant and Husserl will follow in 2023.Social Media and Leibniz’ Monadology Artificial Experience I, workshop, ICI Berlin, 5–6 October 2022 <https://doi.org/10.25620/e221005

The discourse of international standard-setting : PISA tests and Norway, a critical discourse analysis

Peer reviewedPublisher PD

Curriculum for Excellence : A cross-sector investigation of Scottish teachers mathematical befliefs of problem solving

Peer reviewedPublisher PD

Decolonising teacher education

Peer reviewe

Pedagogy in the North : shifting concepts, altered states and common expressions (2)

Peer reviewe

Creative Pedagogies in Uncertain Times : What is Essential? A Conversation with Paul Gorman of Hidden Giants

Peer reviewedPublisher PD

Analysis of multiply spliced transcripts in lymphoid tissue reservoirs of rhesus macaques infected with RT-SHIV during HAART.

Highly active antiretroviral therapy (HAART) can reduce levels of human immunodeficiency virus type 1 (HIV-1) to undetectable levels in infected individuals, but the virus is not eradicated. The mechanisms of viral persistence during HAART are poorly defined, but some reservoirs have been identified, such as latently infected resting memory CD4⁺ T cells. During latency, in addition to blocks at the initiation and elongation steps of viral transcription, there is a block in the export of viral RNA (vRNA), leading to the accumulation of multiply-spliced transcripts in the nucleus. Two of the genes encoded by the multiply-spliced transcripts are Tat and Rev, which are essential early in the viral replication cycle and might indicate the state of infection in a given population of cells. Here, the levels of multiply-spliced transcripts were compared to the levels of gag-containing RNA in tissue samples from RT-SHIV-infected rhesus macaques treated with HAART. Splice site sequence variation was identified during development of a TaqMan PCR assay. Multiply-spliced transcripts were detected in gastrointestinal and lymphatic tissues, but not the thymus. Levels of multiply-spliced transcripts were lower than levels of gag RNA, and both correlated with plasma virus loads. The ratio of multiply-spliced to gag RNA was greatest in the gastrointestinal samples from macaques with plasma virus loads &lt;50 vRNA copies per mL at necropsy. Levels of gag RNA and multiply-spliced mRNA in tissues from RT-SHIV-infected macaques correlate with plasma virus load

Can positive affect induce self-focused attention? Methodological and measurement issues.

Some studies find that positive affect can induce self-focused attention, but other studies find no effect. We suggest that the contrary findings result from how self- awareness was measured. One group of participants listened to happy or neutral music; another group imagined and described a happy or neutral event. Two measures of self-focus were then taken. The experiment replicated past findings: Positive affect increased self-focus on a pronoun selection task, but had no effect on a modified private self-consciousness scale. The results were slightly stronger when affect was induced using music. Implications for future research are discussed. Emotional experience has been closely tied to self-awareness since Duval and Wicklund’s (1972) original statement of objective self-awareness theory. Research has explored the influence of self-focus and self-standard discrepancies on emotion (Ickes, Wicklund, &amp; Ferris, 1973), the effects of self-awareness on emotional intensity (Scheier &amp;Carver, 1977; Silvia, 2002, in press), self-perceptions of emotional states (Silvia &amp; Gendolla, 2001), the role of self-focus in dysfunctional affective experiences (Wells &amp;Matthews, 1994), and the impact of affect on self-evaluation (Berkowitz, 1987; Salovey &amp; Rodin, 1985)