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Impact of ITCZ width on global climate : ITCZ-MIP
Get PDFFunding: This research has been supported by the U.S. Department of Energy Office of Science, Biological and Environmental Research (BER) (grant nos. EESM RGMA DE-SC0022070 and NSF IA 1947282), the National Science Foundation (NSF), Directorate for Geosciences (grant no. AGS-1665247), the Alfred P. Sloan Foundation (research fellowship), the NOAA Climate Program Office (Climate and Global Change Postdoctoral Fellowship), the Natural Sciences and Engineering Research Council of Canada (NSERC postdoctoral fellowship), the Met Office (Hadley Centre Climate Programme funded by DSIT), and the Natural Environment Research Council (grant nos. NE/T003863/1 and NE/W005239/1).The width of the Inter-Tropical Convergence Zone (ITCZ) affects tropical rainfall, Earth's albedo, large-scale circulation, and climate sensitivity. To better understand the ITCZ width and its effects on global climate, we present a protocol to force changes in ITCZ width in climate models. Starting from an aquaplanet configuration with a slab ocean, adding surface heat fluxes in the deep tropics forces the ITCZ to narrow, and subtracting them causes it to widen. The protocol successfully generates changes in ITCZ width in all four climate models used in this study. ITCZ width in each model responds linearly to forcing magnitude and sign. Comparing across the four climate models, a response to varying ITCZ width that is remarkably consistent among models is the ITCZ strength, which is greater the narrower the ITCZ. On the other hand, the effect of varying ITCZ width on climate sensitivity is divergent among our four models, varying even in sign. Results from this pilot study highlight the connections between surface fluxes, ITCZ width, and the wider climate. A comprehensive model intercomparison project (MIP) has the potential to advance understanding of both the physical processes shaping ITCZ width and its influence on remote atmospheric circulations and global climate.Peer reviewe
How do soundboard-trained dogs respond to human button presses? : An investigation into word comprehension
Get PDFFunding: A.P.M.B. is supported by the Johns Hopkins Provost’s Postdoctoral Fellowship Program.Past research on interspecies communication has shown that animals can be trained to use Augmentative Interspecies Communication (AIC) devices, such as soundboards, to make simple requests of their caretakers. The recent uptake in AIC devices by hundreds of pet owners around the world offers a novel opportunity to investigate whether AIC is possible with owner-trained family dogs. To answer this question, we carried out two studies to test pet dogs' ability to recognise and respond appropriately to food-related, play-related, and outside-related words on their soundboards. One study was conducted by researchers, and the other by citizen scientists who followed the same procedure. Further, we investigated whether these behaviours depended on the identity of the person presenting the word (unfamiliar person or dog's owner) and the mode of its presentation (spoken or produced by a pressed button). We find that dogs produced contextually appropriate behaviours for both play-related and outside-related words regardless of the identity of the person producing them and the mode in which they were produced. Therefore, pet dogs can be successfully taught by their owners to associate words recorded onto soundboard buttons to their outcomes in the real world, and they respond appropriately to these words even when they are presented in the absence of any other cues, such as the owner's body language.Peer reviewe
Soundboard-trained dogs produce non-accidental, non-random and non-imitative two-button combinations
Get PDFEarly studies attempting interspecies communication with great apes trained to use sign language and Augmented Interspecies Communication (AIC) devices were limited by methodological and technological constraints, as well as restrictive sample sizes. Evidence for animals' intentional production of symbols was met with considerable criticisms which could not be easily deflected with existing data. More recently, thousands of pet dogs have been trained with AIC devices comprising soundboards of buttons that can be pressed to produce prerecorded human words or phrases. However, the nature of pets' button presses remains an open question: are presses deliberate, and potentially meaningful? Using a large dataset of button presses by family dogs and their owners, we investigate whether dogs' button presses are (i) non-accidental, (ii) non-random, and (iii) not mere repetitions of their owners' presses. Our analyses reveal that, at the population level, soundboard use by dogs cannot be explained by random pressing, and that certain two-button concept combinations appear more often than expected by chance at the population level. We also find that dogs' presses are not perfectly predicted by their owners', suggesting that dogs' presses are not merely repetitions of human presses, therefore suggesting that dog soundboard use is deliberate.Peer reviewe
Geometrically inspired kernel machines for collaborative learning beyond gradient descent
Get PDFFunding: The research reported in this paper has been supported by the state of Upper Austria as part of #upperVISION2030 under the Secure Prescriptive Analytics (SPA) project; Austrian Ministry for Transport, Innovation and Technology, the Federal Ministry for Digital and Economic Affairs, and the State of Upper Austria in the frame of the SCCH competence center INTEGRATE [(FFG grant no. 892418)] part of the FFG COMET Competence Centers for Excellent Technologies Programme. Bowles is partially supported by the Austrian Funding Council (FWF) under Meitner M 3338-N.This paper develops a novel mathematical framework for collaborative learning by means of geometrically inspired kernel machines which includes statements on the bounds of generalisation and approximation errors, and sample complexity. For classification problems, this approach allows us to learn bounded geometric structures around given data points and hence solve the global model learning problem in an efficient way by exploiting convexity properties of the related optimisation problem in a Reproducing Kernel Hilbert Space (RKHS). In this way, we can reduce classification problems to determining the closest bounded geometric structure from a given data point. Further advantages that come with our solution is that our approach does not require clients to perform multiple epochs of local optimisation using stochastic gradient descent, nor require rounds of communication between client/server for optimising the global model. We highlight that numerous experiments have shown that the proposed method is a competitive alternative to the state-of-the-art.Peer reviewe
Self-reported measures of preparedness of graduates of a new remote and rural graduate-entry medical program (ScotGEM)
Get PDFIntroduction : Scotland faces persistent challenges in addressing medical workforce shortages, particularly in remote and rural areas. The Scottish Graduate Entry Medicine (ScotGEM) program was established to address these challenges by training adaptable and resilient medical practitioners with a focus on rural and underserved healthcare settings. Evaluating the preparedness of ScotGEM graduates as they transition into clinical practice is essential for assessing the program's effectiveness. Methods : This study utilised data from the General Medical Council Foundation Year 1 Preparedness Survey, which evaluates newly qualified doctors’ self-reported perceptions of preparedness in key domains: overall preparedness, clinical practical procedures, prescribing and managing acutely unwell patients. Preparedness perceptions of the inaugural ScotGEM cohort were compared to national and Dundee University cohorts using Z-tests for proportions and Cohen’s h to quantify effect sizes. Results : ScotGEM graduates reported levels of preparedness comparable to the national average across all surveyed domains. Specifically, 57.5% of ScotGEM graduates felt adequately prepared for practice (57.9% nationally), 84.6% felt adequately skilled in clinical practical procedures (80.3% nationally), 75.0% reported adequate prescribing skills (79.3% nationally) and 75.0% felt prepared to manage acutely unwell patients (68.4% nationally). Statistical analysis revealed no significant differences between ScotGEM and other cohorts (p>0.05), with small effect sizes (h<0.2) indicating minimal practical differences. Conclusion : ScotGEM graduates demonstrate preparedness levels comparable to their peers nationally and from traditional-entry programs, underscoring the effectiveness of Scotland's first graduate-entry and rurally delivered medical program. Future evaluations with larger sample sizes will be essential to detect subtle differences and further refine ScotGEM’s contributions to Scotland's medical workforce, particularly in underserved areas.Peer reviewe
Callias’ story and the challenges of ‘thinking big’ : Leonardo and Vitruvius write about scale
No full textFjordRPM v1.0 : a reduced-physics model for efficient simulation of glacial fjords
Get PDFFunding: All authors acknowledge support from the UK Natural Environment Research Council (NERC) grant NE/W00531X/1. Donald A. Slater further acknowledges support from NERC grant NE/T011920/1.Interactions between ice masses and the ocean are key couplings in the global climate system. In many cases, these interactions occur through glacial fjords, which are long, deep, and narrow troughs connecting the open ocean to marine-terminating glaciers. By controlling the fluxes of ocean heat towards the ice sheet and ice sheet freshwater towards the ocean, glacial fjords play an important role in modulating ice sheet mass loss and the impacts of freshwater on ocean circulation. Yet, these dynamics occur at small scales that are challenging to resolve in earth system models and hence are often ignored, represented in an ad-hoc manner, or studied using expensive high-resolution models that are limited in scope. Here, we propose a means of capturing glacial fjord dynamics at negligible computational expense in the form of a “reduced-physics” model (FjordRPM) that resembles a “1.5-dimensional” or box model. We describe the design and physical parameterisations in the model and demonstrate its ability to capture important modes of glacial fjord circulation by comparing it against a general circulation model in idealised and realistic simulations. We suggest that the model is a useful tool for understanding fjord dynamics and a promising approach for representing glacial fjord processes within large-scale models or climate and sea level projection efforts.Peer reviewe
Summer bodies
No full text“Summer Bodies” is preoccupied with the physicality of humans and non-humans. In Melissa Febos’s essay “The Return: The Art of Confession,” she writes: “The unspoken parts of experience: the lonely, the existential, the erotic — how was I to know they weren’t mine alone?” Exploring themes of childhood, danger and death, desire, and movement, the poems attempt to put these unspoken experiences into poetry, to document the frustration and joy that refuse to yield to each other. From the strict Shakespearean sonnet to free-verse lowercase poems, this collection draws on personal memories, historical tales and imaginings, while also commenting on what it means to be a being whose body is actively policed by state governments. All bodies have been and still are harmed by past and present policies.
Ballet is one of the central aspects of the manuscript, both explicitly, as in “Bach Suite II” and the longer poem “Swan Lake,” and implicitly, as the institution of ballet shapes dancers’ ability to navigate physical problems, to interpret and act on desire, and to simply spend time outdoors. Ballet traditionally has strict gendered expectations that don’t allow for sexuality, queer or otherwise, to be expressed by women. It is difficult to love what Mary Oliver calls “the soft animal of your body” while surrounded by mirrors and judgement.
Beginning in summer, the poems transition through winter back into summer, a reminder that life is constantly transitioning from one moment to the next, however much we might wish to slow time. Mostly set in America and the United Kingdom, these poems were written during government elections that have resulted in the rolling back of reproductive and gender affirming rights and freedoms previously gained. It would be easy to slip into despair; these poems fight that urge
Heterogeneity or disadvantage? Partnership, childbearing, and employment trajectories of the descendants of immigrants in the United Kingdom
Get PDFFunding: This paper is part of the MigrantLife project that has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 834103)We investigate how partnership, fertility, and employment changes interact in the lives of immigrants’ descendants in the UK. Although these domains are intertwined in individuals’ lives, most studies on migrants and minorities have examined them separately. We apply multi-channel sequence analysis to data from the UK Household Longitudinal Study to establish the main types of joint partnership, fertility, and employment trajectories among the native population and the descendants of immigrants (i.e., 1.5 and second generation). We analyse women and men separately. We find first that the descendants of European/Western immigrants exhibit family and employment trajectories similar to those of the native British population. Second, the descendants of Caribbean immigrants have diverse partnership and fertility patterns, but their employment outcomes are similar or even better compared to those of native women and men. Third, among women of South Asian descent, conservative partnership and family formation patterns are coupled with low labour market attachment. It is not the heterogeneity in partnership and family formation patterns which poses a challenge, rather that these patterns co-exist with low labour market participation. This is likely to have serious long-term implications for the wellbeing of second-generation women.Peer reviewe
Microscopic characterisation of metal nanoparticle exsolution in Ni-doped A-site deficient perovskite titanate
No full textHydrogen technology has been of interest to meet the high demands for the clean, renewable and sustainable energy sources. Solid oxide fuel cells (SOC) have caught the attention because it many advantages including high efficiency and reversibility which enables both production and re-electrification of the hydrogen. Current state of the art SOCs electrodes are based on Ni-YSZ materials but recently research conducting the application of perovskite-based electrode with exsolution have been gaining interest because it can provide improve cell performance and resistance against coking and impurity poisoning as opposed to Ni-YSZ.
Perovskite is known for its unique ability to produce metal nanoparticles on its surface when exposed to high temperatures under a reducing atmosphere which is known as exsolution. The exsolution of perovskite has been suggested as an alternative approach to producing active and durable supported nanoparticle system as it can provide highly active and durable nanoparticles through a simple, single step synthesis procedure that has been limitations of the conventional approaches such as depositions. This made the exsolved perovskite material applicable in a wide range of electrochemical systems includes but not limited to SOC. Understanding the mechanism of exsolution and defect chemistry of perovskite will enable optimisation of the formation of nanoparticles to the need.
This thesis explores characterisation of Ni nanoparticle exsolution in A-site deficient perovskite titanates (Aₒ.₈BO3, A = La³⁺, Sr²⁺, Ca²⁺ and Nd³⁺). First, a series of perovskites with different degree of oxygen vacancies is investigated. Secondly, the influence of Sr²⁺/Ca³⁺ cations on the perovskite exsolution is explored. Lastly, an investigation of the role of rare earth element, Nd³⁺ on the exsolution process is performed. The morphology of the exsolution in each perovskite is compared and analysed with respect to surface orientation. This thesis also demonstrates a quantitative characterisation method through combining EBSD, SEM, FIB and TEM techniques of electron microscopy."I would like to acknowledge Horizon Europe Project 101137604 — EXSOTHyC, supported by UKRI grant number 10102891 and EPSRC Light Element Analysis Facility
Grant EP/T019298/1 and EPSRC Strategic Equipment Resource Grant EP/R023751/1."--Acknowledgement
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