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Impacts of invasive algae from the perspective of fishers in the Lagoon of Venice, Northern Italy
Get PDFInvasive alien species are generally considered a cause of biodiversity decline globally, and studying their evolution could provide valuable insights about their invasion mechanism and impacts to new habitats. The Lagoon of Venice (LV) is a significant gateway for invasive algae introduction into the Adriatic Sea. This work aims to address the pressing need to enhance research on the perceptions of local resource users, especially fishers, on invasive algae impacts on marine resources in the Mediterranean setting. The study conducted between February 2022 and April 2024 involved 31 people, most of whom had been engaged in fishing activities for up to over 60 years, who were interviewed during boat trips and algae collection. Interviewees reported knowledge components, complemented by scientific expertise, related to the invasion mechanisms of algae. Of the 26 identified algae recorded, eight taxa have not yet been reported with their scientific names in surveys on the impact of algae in the LV. Together with perceived reasons and related challenges, environmental impacts, solutions proposed by local fishing experts, and adaptations along with their positive uses are socio-economic impacts which are lacking in the LV scientific surveys. The findings reveal perceptions on the direct and indirect impacts of invasive macroalgae in the LV environment affecting its coastal ecosystem functions. Local fishers' knowledge (LFK) offers many ecologically relevant perspectives, which based on the long-lasting practice could complement scientific knowledge (SK) about the impacts of invasive algae and local stressors related to climate change. Hence, it is vital to integrate the broader knowledge of fishers and include them as equal stakeholders in conservation initiatives.Peer reviewe
FedFreeze : a dual-phase layer freezing framework for federated learning
Get PDFFunding: EPSRC (grant number EP/Y028813/1) and Rakuten Mobile, Inc., Japan.Running Federated Learning (FL) on resource-constrained devices is challenging due to the resources required for training. Layer freezing has been proposed to reduce the computational costs and thus accelerate training. However, we identify that existing layer freezing approaches either learn quickly or learn effectively, but do not balance them. Specifically, aggressive early-stage layer freezing (e.g., AutoFreeze) accelerates training but achieves a lower final accuracy. On the other hand, accuracy-guaranteed layer freezing (e.g., ALF) obtains higher final accuracy but with marginal training time improvement. This article proposes FedFreeze – a dual-phase layer freezing federated learning framework that, for the first time, combines early-stage and accuracy-guaranteed layer freezing into a unified mechanism. FedFreeze designs a novel regularization-based layer freezing strategy on the device to apply early-stage layer freezing even during the initial stages for improving training speedup. In addition, FedFreeze develops a convergence-based layer freezing strategy to achieve a high final accuracy. Experimental results show that the proposed FedFreeze framework achieves up to 1.3 × training speedup while limiting the accuracy drop to no more than 1.67 % compared to vanilla FL. In contrast to state-of-the-art early-stage and accuracy-guaranteed layer freezing methods, FedFreeze consistently strikes a better balance between efficiency and accuracy across a wide range of settings, including different hardware platforms (Raspberry Pi and Jetson Nano clusters), datasets (FMNIST, CIFAR-10, CIFAR-100), model architectures (AlexNet, VGG11, ResNet12), and initialization strategies. The results demonstrate that FedFreeze outperforms state-of-the-art layer freezing techniques in accelerating FL training on resource-constrained devices, without incurring significant accuracy loss.Peer reviewe
Widespread carbon-dense peatlands in the Colombian lowlands
Get PDFFunding: King Center on Global Development at Stanford University (R S W, A M H). Swiss National Science Foundation grant 190328 (R S W). NERC Knowledge Exchange Fellowship grant NE/V018760/1 and NE/V018760/2 (E N H C). International Max Planck Research School for Global Biogeochemical Cycles (A U). European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme grant agreement No 865403 (A G S). Charles University (PRIMUS/23/SCI/013), Charles University Research Centre program (UNCE/24/SCI/006) and the OP JAK programme ‘Natural and anthropogenic geohazards’ (CZ.02.01.01/00/22_008/0004605) (A H). National Science Foundation award 2406964 (A M H). National Academy of Sciences NAS-PEER grant sub-award 2000012206 (J C B D).Peatlands are some of the world’s most carbon-dense ecosystems and release substantial quantities of greenhouse gases when degraded. However, conserving peatlands in many tropical areas is challenging due to limited knowledge of their distribution. To address this, we surveyed soils and plant communities in Colombia’s eastern lowlands, where few peatlands have previously been described. We documented peat soils >40 cm thick at 51 of more than 100 surveyed wetlands. We use our data to update a regional peatland classification, which includes a new and possibly widespread peatland type, ‘the white-sand peatland,’ as well as two distinctive open-canopy sub-types. Analysis of peat bulk density and organic matter content from 39 intact peat cores indicates that the average per-area carbon densities of these sites (490–1230 Mg C ha−1, depending on type) is 4–10 times the typical carbon stock of a (non-peatland) Amazonian forest. We used remote sensing to upscale our observations, generating the first data-driven peatland map for the region. The total estimated carbon stock of these peatlands of 1.91 petagrams (Pg C) (2-sigma confidence interval, 0.60–4.22) approaches that of South America’s largest known peatland complex in the northern Peruvian Amazon, indicating that substantial peat carbon stores on the continent have yet to be documented. These observations indicate that tropical peatlands may be far more diverse in form and structure and broadly distributed than is widely understood, which could have important implications for tropical peatland conservation strategies.Peer reviewe
A defense of Aristotelian eudaimonia
Get PDFEm Two Conceptions of Happiness, Richard Kraut denuncia a desumanidade e restritividade da eudaimonia aristotélica. O presente artigo oferece uma crítica à avaliação de Kraut. A primeira parte do artigo, de caráter exegético, disputa a interpretação intelectualista que Kraut faz da eudaimonia e propõe uma leitura dualista da mesma que procura resolver os maiores problemas do debate clássico entre inclusivistas e intelectualistas. A segunda parte do artigo, por sua vez, defende uma forma de objetivismo contra a concepção subjetiva de felicidade exposta por Kraut: primeiro, argumentando que as acusações de Kraut se aplicam tanto à eudaimonia quanto à sua concepção subjetiva de felicidade sendo que, no caso da última, é impossível lidar com casos de comportamento vicioso “feliz” que são, numa concepção eudaimônica, facilmente descartados; segundo, demonstrando que o subjetivismo de Kraut é, na verdade, um objetivismo velado: na sua tentativa de ir além de uma concepção meramente psicológica de felicidade, Kraut viu-se obrigado a enriquecer normativamente o conceito de felicidade com critérios que vão além das determinações do sujeito. Concluímos assim que a eudaimonia aristotélica nos continua a fornecer a única alternativa cabal a uma visão puramente psicológica de felicidade, sendo, portanto, ainda relevante no debate ético.Peer reviewe
Single-crystal X-ray diffraction studies of derivatives of phenolphthalein (3,3-bis(4-hydroxyphenyl)isobenzofuran-1(3H)-one)
Get PDFAn investigation of the molecular structure of a series of phenolphthalein derivatives is presented. The X-ray structures of thymolphthalein, 2,5-dimethylphenolphthalein, and 2,6-dimethylphenolphthalein have been determined for the first time. Furthermore, a series of related 3-(4-hydroxy-dialkyl)-3-(4-hydroxyphenyl)isobenzofuran-1(3H)-ones have also been prepared, and X-ray structures obtained. The present study allows for comparison of the structures of substituted phenolphthalein derivatives, with a particular focus on the effect of different alkyl groups on the structures.Peer reviewe
Men’s impulsivity underpins gender differences in aggressive behaviour
Get PDFFunding: The project leading to these results has received doctoral student funding from the University of St Andrews.The relationship between gender and aggression is multi-faceted, with survey research showing that the aggression varies with the gender of both aggressor and target. Here, using a lab-based paradigm that controls the capacity to cause harm and the risk of retaliation, we reveal pronounced gender-specific differences in aggression. Reactive aggression was assessed using a competitive reaction-time task that allowed dyadic pairs to interact face-to-face during conflict. Across two studies (n = 162/trials = 5099) same- and mixed-gender familiar pairs blasted each other repeatedly with noxious sounds, producing an oscillatory pattern of escalating and de-escalating aggression. Analysis revealed lower aggression in dyads made up of two women than mixed dyads or those made up of two men. Crucially, men were an order of magnitude more likely than women to initiate increases in aggression, and brief experimentally imposed delays designed to block impulsive behaviour significantly reduced male aggression. Put simply, when higher levels of aggression were seen, men (usually) started it.Peer reviewe
Strontium-free Ruddlesden–Popper cuprates (La1.7Ca0.3Cu0.75M0.25O4+δ, M = Fe, Co, Ni) as cathode materials for high-performance solid oxide fuel cells
Get PDFFunding: This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP), with financial resources granted by the Ministry of Trade, Industry & Energy (MOTIE) (grant numbers 20213030030220 and 2024004321240). Additionally, it was supported by the Technology Innovation Programs (RS-2024-00432124 and RS-2024-00469244) from the Korea Evaluation Institute of Industrial Technology (KEIT) and MOTIE of the Republic of Korea.Ruddlesden–Popper phases of the K2NiF4 type exhibit anisotropic lattice-oxygen mobility and hold promise as cathode materials for solid oxide fuel cells (SOFCs). However, most of these phases suffer from cation (e.g., Sr2 +) segregation, which hinders their commercialization. To overcome this limitation, we herein prepared Sr-free perovskite cuprates of La1.7Ca0.3Cu0.75M0.25O4+δ (M = Cu, Co, Ni, Fe) and investigated the influence of M on their lattice structure and their performance as SOFC cathode materials. The highest performance was achieved for M = Co, in which case an optimized Sc-stabilized-zirconia/Ni-YSZ-anode-supported cell without a buffer layer between the cathode and electrolyte delivered maximum power densities of 2.57 and 1 W cm−2 at 850 and 750 °C, respectively, and did not suffer from cation segregation. Thus, our work paves the way for the development of next-generation SOFCs and establishes important composition–structure–activity relationships for their cathode materials.Peer reviewe
Towards a process of translational palaeoecology : a practical guide to research co-production
Get PDFFunding: This research was conducted as part of Jessica Gauld's PhD at the University of Manchester with financial support from the University of Manchester's President's Doctoral Scholar award.1. Palaeoecology has the potential to support practical conservation, offering a long-term perspective to issues such as biodiversity loss, environmental restoration and peatland carbon storage. However, achieving a widespread and effective application of palaeoecology within conservation practice requires greater and more efficient collaboration between academics, practitioners and policymakers. 2. Translational palaeoecology offers a methodological approach to achieve collaboration between academia and conservation and produce palaeoecological research that can support and inform conservation action. 3. This paper reports the results of a workshop involving academics undertaking palaeoenvironmental research and conservation practitioners concerning the barriers and practical recommendations for effective research-practice collaboration. The experiences of the participants highlight the benefits of a collaborative approach for producing palaeoecological research that is enriched with experiential and contextual knowledge. Key themes emerging from the workshop include the importance of mutual learning and knowledge exchange, and supporting practitioners to be co-researchers. 4. Practical implication. The workshop outcomes are presented as a framework of practical guidelines for implementing translational palaeoecology. Key recommendations for academics include engaging with practitioner activities as relationship-building opportunities, utilising field visits for knowledge exchange, adopting a knowledge facilitation role or involving a facilitator to support practitioner understanding, using workshops to explore the practical relevance of palaeoecological data and enabling practitioners to communicate palaeo-research findings in their sphere. Key recommendations for practitioners include inviting academics to practitioner meetings, providing tacit and experiential knowledge throughout the process, exploring practitioner- or land-owner-led funding opportunities for translational research and partaking in communication roles for wider dissemination of research.Peer reviewe
Empire in flux : the managing of otherness and the creation of Swedishness during periods of territorial expansion and decline, 1645–1845
No full textIn this thesis, I examine the management of otherness and the creation of Swedishness through the lens of writers who were working on behalf of the Swedish state, between 1645 (the Second Treaty of Brömsebro) and 1845 (the termination of Götiska Förbundet (the Gothic League)). As these writers dealt with territorial fluctuations, they created narratives of both belonging and exclusion as they produced knowledge on behalf of the Swedish Empire. These concepts are studied in the context of history writing in the expansionist period with reference to Olof Rudbeck the Elder and Samuel Pufendorf. Additionally, they are examined in the context of imperial decline in the natural sciences by studying the work of Olof Rudbeck the Younger, Carl Linnaeus, and Kungliga Vetenskapsakademien (the Royal Swedish Academy of Sciences), in narratives of the past as presented by competition entries to Kungliga Vitterhetsakademien (the Royal Swedish Society of Letters, History and Antiquities), and in the development of national romanticism through Götiska Förbundet. This thesis places Sweden within the context of empire studies and contributes to scholarship on national belonging and identity. I draw several broader conclusions about constructions of Swedishness and otherness. The concept of Swedishness was stable within the core of Sweden proper. The key exception to this occurred in the treatment of Sápmi. During the decline of the empire, there was a growing interest in incorporating the Northern land in a way which could be productive for the rest of Sweden. This was a practical and scientific, rather than a cultural endeavour. The treatment of those considered “Other” was also consistent; when discussing Finns and Sámi, they were presented as different from “true” Swedes. This was especially stressed after the loss of Finland, where the emphasis on a Gothic-based identity meant that Finland did not need to be engaged
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