179566 research outputs found
Sort by
Last Millennium Volcanic Forcing and Climate Response using SO Emissions
Get PDFClimate variability in the last millennium (past 1000 years) is dominated by the effects of large-magnitude volcanic eruptions; however, a long-standing mismatch exists between model-simulated and tree-ring-derived surface cooling. Accounting for the self-limiting effects of large sulfur dioxide (SO2) injections and the limitations in tree-ring records, such as lagged responses due to biological memory, reconciles some of the discrepancy, but uncertainties remain, particularly for the largest tropical eruptions. The representation of volcanic forcing in the latest generation of climate models has improved significantly, but most models prescribe the aerosol optical properties rather than using SO2 emissions directly and including interactions between the aerosol, chemistry, and dynamics. Here, we use the UK Earth System Model (UKESM) to simulate the climate of the last millennium (1250–1850 CE) using volcanic SO2 emissions. Averaged across all large-magnitude eruptions, we find similar Northern Hemisphere (NH) summer cooling compared with other last-millennium climate simulations from the Paleoclimate Modelling Intercomparison Project Phase 4 (PMIP4), run with both SO2 emissions and prescribed forcing, and a continued overestimation of surface cooling compared with tree-ring reconstructions. However, for the largest-magnitude tropical eruptions in 1257 (Mt. Samalas) and 1815 (Mt. Tambora), some models, including UKESM1, suggest a smaller NH summer cooling that is in better agreement with tree-ring records. In UKESM1, we find that the simulated volcanic forcing differs considerably from the PMIP4 dataset used in models without interactive aerosol schemes, with marked differences in the hemispheric spread of the aerosol, resulting in lower forcing in the NH when SO2 emissions are used. Our results suggest that, for the largest tropical eruptions, the spatial distribution of aerosol can account for some of the discrepancies between model-simulated and tree-ring-derived cooling. Further work should therefore focus on better resolving the spatial distribution of aerosol forcing for past eruptions
Creativity Embedded in the Biology Curriculum
Get PDFThis article describes an intervention that was implemented in a School of Biological Sciences to improve students’ attitudes and experiences of creativity in learning. Initial surveys showed that our students did not feel that there were sufficient opportunities for creativity within their curriculum and that many students did not recognise their own creative potential. Given the importance of creativity to student learning, and to their futures, we designed a series of activities to encourage student creativity and embedded the activities within the first semester of our core biology first-year curriculum. Activities were designed to develop four overlapping aspects of student learning: i) to value creativity, ii) to appreciate the connection between creativity and learning biology, iii) to build students’ self-belief in their own creative potential and iv) to develop their creative skills. We share our reflections as staff members delivering this intervention in two course iterations. We then present examples of student outputs, feedback comments, and personal reflections from students’ reflective portfolios. Finally, we discuss key lessons learned and offer closing thoughts on the integration of creativity into our biology curriculum
In defence of normic de minimis expected utility theory
Get PDFIn a recent paper, Björn Lundgren and H. Orri Stefánsson (forthcoming) present three objections to normic de minimis expected utility theory (NDEUT) – a decision theoretic framework defended in Smith (2024). In this paper, I respond to these objections and outline some possible ways in which NDEUT might be modified or further developed. Like any de minimis framework, NDEUT employs a risk threshold to sort possibilities into those that must be considered when making a decision, and those that can be legitimately ignored – the so-called ‘de minimis risks’. While this threshold would usually take the form of a probability value, in NDEUT the de minimis risks are identified instead on the basis of their abnormality. In the first section I will set up some of the formalism used in NDEUT and consider Lundgren and Stefánsson’s first objection – which is essentially formal in nature. In the second section I will delve further into the interpretation of NDEUT and consider the second and third objections, which turn on particular examples
“The Three Musketeers”:A triadic analysis of parenting responsibilities within UK LGBTQ+ three-parent families
Get PDFWithin the United Kingdom, alongside many other countries, it is legally and socially assumed that every child is born with two parents. Recently, there has been an increased societal interest in intentional multiparent families, where more than two adults are actively involved in coparenting a child, yet little research has explored experiences within these families. This study addresses this gap, exploring the way in which parenting roles and responsibilities are negotiated within lesbian, gay, bisexual, trans, queer and questioning intentional three-parent families in the United Kingdom. This article draws upon a unique data set of threeparent families, including interviews with 12 lesbian, gay, bisexual, trans, queer and questioning parents in four families in the United Kingdom. Data were analyzed using a novel analytical approach, qualitative triadic analysis, which allows for the analysis of participants’ experiences at an individual and family level. Family systems theory and the underutilized theoretical concept of emotional triangles were used to make sense of the data. Three themes were identified in the data, all addressing the research question “How do three-parent families negotiate parenting roles and responsibilities?” Findings highlight that participants managed their parenting arrangement in two different ways, either sharing parenting responsibilities equally or dividing parenting roles, with primary and secondary caregivers taking on different responsibilities. Participants discussed the importance of flexibility and communication in managing their arrangement and all participants reported positive coparenting relationships. This study has a number of implications: Methodologically and theoretically, this study highlights the usefulness of systemic qualitative approaches to studying diverse families. Legally, findings highlight the restrictiveness of two-parent models.</p
Human-correlated genetic models identify precision therapy for liver cancer
Get PDFHepatocellular carcinoma (HCC), the most common form of primary liver cancer, is a leading cause of cancer-related mortality worldwide 1,2. HCC occurs typically from a background of chronic liver disease, caused by a spectrum of predisposing conditions. Tumour development is driven by the expansion of clones that accumulate progressive driver mutations 3, with hepatocytes the most likely cell of origin 2. However, the landscape of driver mutations in HCC is broadly independent of the underlying aetiologies 4. Despite an increasing range of systemic treatment options for advanced HCC, outcomes remain heterogeneous and typically poor. Emerging data suggest that drug efficacies depend on disease aetiology and genetic alterations 5,6. Exploring subtypes in preclinical models with human relevance will therefore be essential to advance precision medicine in HCC 7. Here we generated a suite of genetically driven immunocompetent in vivo and matched in vitro HCC models. Our models represent multiple features of human HCC, including clonal origin, histopathological appearance and metastasis. We integrated transcriptomic data from the mouse models with human HCC data and identified four common human–mouse subtype clusters. The subtype clusters had distinct transcriptomic characteristics that aligned with the human histopathology. In a proof-of-principle analysis, we verified response to standard-of-care treatment and used a linked in vitro–in vivo pipeline to identify a promising therapeutic candidate, cladribine, that has not previously been linked to HCC treatment. Cladribine acts in a highly effective subtype-specific manner in combination with standard-of-care therapy.</p
Towards scalable and cost-effective RAN emulation leveraging the public cloud
Get PDFThe rise of data-driven and AI-powered monitoring in 5G and beyond has created a need for RAN digital twins to test and enhance network performance without disrupting real-world operations. However, large-scale RAN emulation remains challenging due to the complexity of the RAN protocol stack and the high cost of hardware-based solutions. Software alternatives are more affordable but current solutions sacrifice fidelity or scalability. This paper presents Chronos, a cloud-based RAN emulation system that overcomes these challenges by abstracting the compute-intensive PHY layer, virtualizing emulation time, RAN slot level synchronization and scalable switch based traffic forwarding. Experiments using OpenAirInterface based prototype on public cloud infrastructure demonstrate Chronos' ability to emulate 250 base stations and 1000 UEs with 468 CPU cores at high fidelity, reflecting its potential for enabling scalable RAN emulation in an affordable manner
The World is Not Enough: Growing waste in HPC-enabled academic practice
Get PDFMost research depends to some extent on technologies and computational infrastructures including, and perhaps especially, HCI. Despite the noted environmental impacts associated with information communication technology (ICT) globally, to date little consideration has been given as to how to limit the impact of research and innovation processes themselves. Working to understand the technical and cultural drivers of this impact within the specific but resource-intensive domain of High Performance Computing (HPC), we conducted 25 interviews with academic researchers, providers, funders, and commissioners of HPC. We find intersecting socio-cultural and technical dimensions that link to research institutions like conferences, funders, and universities that reinforce and embed, rather than challenge, expectations of growth and waste. At a time when large scale cloud systems, generative AI and ever larger models are multiplying, we argue to de-escalate demand for computing, aiming for more moderate, responsible and meaningful use of computational infrastructures - including within HCI itself.</p
Ghost segments in Sengwer nouns
Get PDFLike other Kalenjin languages, Sengwer has a complex and understudied noun morphology which makes use of an abundance of affixes as well as word-internal tone and ATR changes. In addition, its nominal inflectional paradigms are teeming with unexpected stem-final segments which appear in certain morphological conditions but are absent in others. The phonological composition of this stem-final latent material is not predictable and varies from noun to noun—C, V, CV and even CCV are all possible. This paper provides a first description of the form and distribution of these segments as well as a novel analysis of their behaviour which explains much of the variation and irregularity seen in nominal inflection. In particular, this paper presents evidence that, although some of these latent segments are part of the root, others are part of suffixes and others still are morphologically active suffixes in their own right. In a departure from earlier studies, we argue that these segments should not be analysed as being inserted thematic material and are better understood as deleted ghost segments instead. Though the term ghost refers to a common phenomenon cross-linguistically, it has been characterised using different labels (e.g., latent, liaison, floating) depending on the tradition and the element affected. Building on Zimmermann’s (2019) definition of ghosts, we argue that these phenomena do not only occur to satisfy synchronic phonological constraints but can also be the result of historical processes no longer at work
Hepatic stellate cells control liver zonation, size and functions via Rspo3
Get PDFHepatic stellate cells (HSCs) have a central pathogenetic role in the development of liver fibrosis. However, their fibrosis-independent and homeostatic functions remain poorly understood 1-5. Here we demonstrate that genetic depletion of HSCs changes WNT activity and zonation of hepatocytes, leading to marked alterations in liver regeneration, cytochrome P450 metabolism and injury. We identify R-spondin 3 (RSPO3), an HSC-enriched modulator of WNT signalling, as responsible for these hepatocyte-regulatory effects of HSCs. HSC-selective deletion of Rspo3 phenocopies the effects of HSC depletion on hepatocyte gene expression, zonation, liver size, regeneration and cytochrome P450-mediated detoxification, and exacerbates alcohol-associated and metabolic dysfunction-associated steatotic liver disease. RSPO3 expression decreases with HSC activation and is inversely associated with outcomes in patients with alcohol-associated and metabolic dysfunction-associated steatotic liver disease. These protective and hepatocyte-regulating functions of HSCs via RSPO3 resemble the R-spondin-expressing stromal niche in other organs and should be integrated into current therapeutic concepts. </p
Access Repository Dashboard
Do you manage Edinburgh Research Explorer? Access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard!