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Planning the operation of Li-Ion battery-powered trucks
No full textThis paper analyses the planning of operations for underground mining trucks powered by lithium-ion batteries. Trucks supplied by the companies Epiroc and Sandvik are used as examples, comparing their characteristics with equivalent diesel-engine models. These trucks have similar payload capacities and dimensions, but significant differences in available energy, demonstrating that battery-powered trucks have substantially lower autonomy. The paper describes a method for estimating the autonomy of battery-powered trucks, considering motor efficiency, energy losses, and regenerative braking. A procedure is presented for determining the energy consumption for truck movement along a known route, considering the total resistance. It is demonstrated that the lower available energy of battery-powered trucks is a major factor necessitating a different approach to planning their operation in underground mining
Multi Hazards Early Warning Systems Forum - WMO:No time to waste: The race for effective multi-hazard early warning systems in fragile and conflict settings
No full textAs compound risks and climate hazards increasingly threaten populations most at risk in fragile, conflict-affected and violence-prone contexts, the need for effective Multi-Hazard Early Warning Systems (MHEWS) has never been more urgent. Despite significant challenges, recent advances such as the COP28 Declaration, new research and growing momentum around anticipatory action offer promising pathways forward.This session brings together a diverse lineup of speakers to explore practical, scalable solutions that can turn MHEWS into a lifeline in the most complex settings. Participants will gain valuable insights from the latest policy, research and field-based practices alongside innovative financing mechanisms, helping to identify critical gaps and untapped opportunities.Join us for an inspiring and solutions-driven discussion aimed at transforming early warnings into early action for communities on the frontlines
Making the Invisible Visible:A Molecular View on Early Stage Protein Aggregation of α-Synuclein
No full textNeurodegenerative diseases (NDs) pose a growing global health challenge, with protein aggregation as a central hallmark. In Parkinson’s disease (PD), the intrinsically disordered protein α-synuclein (αS) aggregates into amyloid fibrils. While fibrils have been extensively studied, the early aggregation mechanisms remain elusive. This thesis focuses on the formation and modulation of αS multimers – transient, pre-amyloid intermediates that may act as regulatory or pathological precursors.Using single-molecule and bulk fluorescence spectroscopy, combined with computational and biochemical approaches, we assess the full αS aggregation pathway from monomer to fibril, with emphasis on the multimeric stages and their regulation by protein quality control (PQC) systems. Initial method development enabled probing of αS at the single-molecule level, revealing how local sequence features modulate its disordered conformations. We then demonstrated that αS self-assembles into dynamic, liquid-like multimers at sub-micromolar concentrations. These nanoscale assemblies share hallmarks with biomolecular condensates and support a unified phase-transition model of aggregation, where condensation and deposition pathways differ mainly by the length scale of their intermediate states: microscale droplets versus nanoscale multimers.Physiological modulators, including sequence elements and post-translational modifications, were found to tune multimerization without affecting fibril formation – underscoring its mechanistic distinctness. PQC systems likely target this gateway step. Indeed, the chaperone-like protein 14-3-3τ selectively engages αS multimers to form smaller, off-pathway co-condensates, preventing further aggregation. Phosphorylation at Serine-129 enhances this co-assembly via non-canonical multivalent interactions, highlighting a tuneable mechanism that may preserve protein homeostasis.Altogether, this thesis advances an integrated view of αS aggregation, from monomer to multimer to fibril, and identifies early multimers as important regulatory nodes. By unveiling these previously “invisible” species, this work reveals novel mechanisms and therapeutic entry points acting at the onset, rather than the aftermath, of pathological protein aggregation in neurodegenerative disease.<br/
Patient-Specific Size and Age Scaling in a Zero Dimensional Cardiovascular Model
No full textComputational cardiovascular models hold promise for simulations in education and bedside clinical decision support. To enhance patient-specific modeling, individual anthropometrics are imperative, as physiology varies with body size due to fundamental energetic relations expressed in allometric scaling laws. We hypothesize that computational cardiovascular models can be advanced towards individualization by implementing scaling laws based on patient age, weight, height, and sex. A scaling methodology was developed for the lumped-parameter cardiovascular model Aplysia Cardiovascular Lab. Male and female subjects were based on Swedish growth charts from birth to adult size and simulated to test model realism. Realistic physiology was generated for underweight, overweight, and average male and female patients from birth to 80 years. Model output included comprehensive measures of hemodynamics, cardiac function, respiratory function, gas exchange, ventilatory mechanics, and energy expenditure. In comparison to published data, aggregate Z scores for infant, pediatric, and geriatric simulations were 1.16, 0.69, and 0.10, respectively. Allometric scaling laws can be used to generate parameter sets of males and females of disparate sizes and ages in line with published data. This sets the stage for modeling diverse patient populations and novel approaches toward individualized clinical applications.</p
High-impact low-probability events: Exposure to potential large-magnitude explosive volcanic eruptions
No full textThe Park Multiple:Practices of Coordination in a Conservation-Tourism Partnership in South Africa
No full textConservation–tourism partnerships are often promoted as win–win solutions to the twin problems of underfunded conservation and unsustainable development. Critics on the other hand have warned about the tendency toward win–lose outcomes, when nature is reduced to a tourism commodity. This article intervenes in this debate by contributing to a scholarship in Science and Technology Studies on ontological multiplicity. We present an ethnographic case study of a nature park in South Africa that analyzes its partnership and its outcomes as emerging from situated and messy political dynamics. Our findings demonstrate the ontological politics taking place in the interactions between two enacted versions of the park: a tourism version and a conservation version. We show how in some cases one version comes to matter over the other and also how the outcomes of these ontological politics are not total. In doing so, our analysis furthers the study of ontological multiplicity of natural places by going beyond the mapping of multiplicity, to also explicitly consider power relations. Focusing on the work of coordination, we challenge both win–win and win–lose accounts of conservation–tourism partnerships, revealing possibilities for doing partnerships otherwise. We also make the argument for expanding these possibilities through a move toward “response-able” tourism
Unveiling the effect of adding B<sub>4</sub>C at the W-on-Si interface
No full textW/Si thin-film structures are used in various applications, including X-ray optics. While many studies reported that adding a sub-nm-thick B4C film at the W/Si interfaces is beneficial for the overall reflectivity of the structures, the physical mechanisms involved were not yet fully understood. In this study, we investigate the W-on-Si interface and the effect of adding a B4C interlayer at such interface, using low-energy ion scattering (LEIS) spectroscopy, X-ray reflectivity, X-ray diffraction, and transmission electron microscopy with energy dispersive X-ray spectroscopy. We extract the effective width of the interface in three different structures having: no-B4C, 0.24 nm, and 1.2 nm of B4C deposited between the W and the Si films. The analysis reveals that the W distribution does not get significantly sharper when B4C atoms are deposited at the W-on-Si interface, showing that B4C does not act as a physical barrier against the diffusion of atoms during the deposition of these structures. This study highlights the importance of systematically extracting the values of the effective interface width for the analysis and understanding of thin-film growth, which is highly valuable for the design of multilayer optics in soft X-ray applications.</p
Hierarchical event segmentation of episodic memory in virtual reality
No full textContextual shifts are crucial for episodic memory, setting event boundaries during event segmentation. While lab research provides insights, it often lacks the complexity of real-world experiences. We addressed this gap by examining perceptual and conceptual boundaries using virtual reality (VR). Participants acted as salespeople, interacting with customers in a VR environment. Spatial boundaries separated visually distinct booths, while conceptual boundaries were defined by customer requests. Memory was assessed through a recency discrimination task. Results indicated boundary crossings impaired sequence memory, consistent with previous findings. Crucially, conceptual boundaries, but not spatial boundaries, significantly influenced the accuracy of sequence memory, suggesting that top-down processes dominate bottom-up perceptual processes in naturalistic event segmentation. Confidence in correct responses indicated that perceived memory quality was highest when participants stayed within and did not cross both spatially and conceptually defined events. Findings highlight VR’s effectiveness for studying hierarchical contextual influences in interactive episodic memory tasks.</p
Haunted by hunting:A landscape geneology of the biopolitics, necropolitics, and sovereign power of red deer and wild boar management at the Veluwe
No full textThe Veluwe is considered as one of the most important nature areas in the Netherlands. Its public appeal in part derives from the presence of large ungulates, such as red deer and wild boar. These populations of red deer and wild boar are caught up in management practices and spaces of control that have emerged as part of the history of the Veluwe as an elite hunting reserve, including material practices and imaginations of nature and culture. Historically, these deer and boars were considered to be hunting animals, but now they are killed under the name of wildlife management. Yet, the hunting histories of this space persist through certain landscapes, particular animal species and breeds, discourses and symbolic meanings, resulting in the production of particular biopolitical subjects and objects. In this article, we draw on an ethnography of these hunting landscapes and historical and archival research to trace the genealogy of the ways in which certain forms of bio-, necro-, and sovereign power are inscribed into the landscape of the Veluwe and how these forms of power continue to play a role in the lives and deaths of these animals today. The case of the Veluwe contributes to a growing understanding of how conservation in many places has emerged as part of elite hunting practices.</p
Financial toxicity and socioeconomic impact of cancer in Europe
No full textBackground: Even with universal health care, patients living with cancer often face substantial treatment-related costs and income loss in Europe. Insights into the socioeconomic impact of cancer within and across countries are needed to create awareness, inform policy, and develop targeted measurement instruments. The SEC study aims to explore the socioeconomic impact and financial toxicity of cancer and identify vulnerable patient groups across Europe. Patients and methods: To investigate experiences of a large number of patients, data were collected in a collaborative effort of hospitals and patient organizations across Europe through convenience sampling. Patients undergoing treatment currently or treated within the past 2 years could participate. A 44-item survey was developed to measure the socioeconomic impact following a cancer diagnosis. The primary outcome was the level of financial toxicity, measured by the Financial Index of Toxicity (FIT) score. To identify vulnerable groups, multiple regression analyses were used to investigate the association between the FIT score, clinical characteristics, and socioeconomic demographics, including cancer type, employment status, and country of residence. Results: A total of 2507 patients across Europe met the inclusion criteria. Fifty-six percent of the patients reported income loss and 86% additional treatment-related expenses. Sixteen percent of patients delayed or avoided medical visits, buying medication, surgery, or other health services. Next to a significant association of the country of residence, our regression models demonstrated that divorced, self-employed patients who were younger (−0.02; P = 0.000) and lower educated (0.75; P = 0.000) with a lower household income (1.21; P = 0.000) and children (0.21; P = 0.000) at the time of diagnosis reported significantly higher FIT scores compared with older patients who were married (−0.56; P = 0.000), retired (−1.55; P = 0.000), or employed (−0.56; P = 0.000). Conclusions: In every European Union country, a substantial number of patients with cancer report serious financial consequences and stress. Further research is critical to inform well-tailored policies and interventions to limit the socioeconomic impact on patients with cancer.</p