| 1. |
|
|
| 2. |
- Fenstermacher, M.E., et al.
(author)
-
DIII-D research advancing the physics basis for optimizing the tokamak approach to fusion energy
- 2022
-
In: Nuclear Fusion. - : IOP Publishing. - 0029-5515 .- 1741-4326. ; 62:4
-
Journal article (peer-reviewed)abstract
- DIII-D physics research addresses critical challenges for the operation of ITER and the next generation of fusion energy devices. This is done through a focus on innovations to provide solutions for high performance long pulse operation, coupled with fundamental plasma physics understanding and model validation, to drive scenario development by integrating high performance core and boundary plasmas. Substantial increases in off-axis current drive efficiency from an innovative top launch system for EC power, and in pressure broadening for Alfven eigenmode control from a co-/counter-I p steerable off-axis neutral beam, all improve the prospects for optimization of future long pulse/steady state high performance tokamak operation. Fundamental studies into the modes that drive the evolution of the pedestal pressure profile and electron vs ion heat flux validate predictive models of pedestal recovery after ELMs. Understanding the physics mechanisms of ELM control and density pumpout by 3D magnetic perturbation fields leads to confident predictions for ITER and future devices. Validated modeling of high-Z shattered pellet injection for disruption mitigation, runaway electron dissipation, and techniques for disruption prediction and avoidance including machine learning, give confidence in handling disruptivity for future devices. For the non-nuclear phase of ITER, two actuators are identified to lower the L-H threshold power in hydrogen plasmas. With this physics understanding and suite of capabilities, a high poloidal beta optimized-core scenario with an internal transport barrier that projects nearly to Q = 10 in ITER at ∼8 MA was coupled to a detached divertor, and a near super H-mode optimized-pedestal scenario with co-I p beam injection was coupled to a radiative divertor. The hybrid core scenario was achieved directly, without the need for anomalous current diffusion, using off-axis current drive actuators. Also, a controller to assess proximity to stability limits and regulate β N in the ITER baseline scenario, based on plasma response to probing 3D fields, was demonstrated. Finally, innovative tokamak operation using a negative triangularity shape showed many attractive features for future pilot plant operation.
|
|
| 3. |
- Falster, Daniel, et al.
(author)
-
AusTraits, a curated plant trait database for the Australian flora
- 2021
-
In: Scientific Data. - : Nature Portfolio. - 2052-4463. ; 8:1
-
Journal article (peer-reviewed)abstract
- We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field campaigns, published literature, taxonomic monographs, and individual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge.
|
|
| 4. |
- Manni, Giovanni Li, et al.
(author)
-
The OpenMolcas Web : A Community-Driven Approach to Advancing Computational Chemistry
- 2023
-
In: Journal of Chemical Theory and Computation. - : American Chemical Society (ACS). - 1549-9618 .- 1549-9626. ; 19:20, s. 6933-6991
-
Journal article (peer-reviewed)abstract
- The developments of the open-source OpenMolcas chemistry software environment since spring 2020 are described, with a focus on novel functionalities accessible in the stable branch of the package or via interfaces with other packages. These developments span a wide range of topics in computational chemistry and are presented in thematic sections: electronic structure theory, electronic spectroscopy simulations, analytic gradients and molecular structure optimizations, ab initio molecular dynamics, and other new features. This report offers an overview of the chemical phenomena and processes OpenMolcas can address, while showing that OpenMolcas is an attractive platform for state-of-the-art atomistic computer simulations.
|
|
| 5. |
- Abend, Sven, et al.
(author)
-
Terrestrial very-long-baseline atom interferometry : Workshop summary
- 2024
-
In: AVS Quantum Science. - : American Institute of Physics (AIP). - 2639-0213. ; 6:2
-
Research review (peer-reviewed)abstract
- This document presents a summary of the 2023 Terrestrial Very-Long-Baseline Atom Interferometry Workshop hosted by CERN. The workshop brought together experts from around the world to discuss the exciting developments in large-scale atom interferometer (AI) prototypes and their potential for detecting ultralight dark matter and gravitational waves. The primary objective of the workshop was to lay the groundwork for an international TVLBAI proto-collaboration. This collaboration aims to unite researchers from different institutions to strategize and secure funding for terrestrial large-scale AI projects. The ultimate goal is to create a roadmap detailing the design and technology choices for one or more kilometer--scale detectors, which will be operational in the mid-2030s. The key sections of this report present the physics case and technical challenges, together with a comprehensive overview of the discussions at the workshop together with the main conclusions.
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
- Park, D. S., et al.
(author)
-
The emergence of magnetic ordering at complex oxide interfaces tuned by defects
- 2020
-
In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723 .- 2041-1723. ; 11:1
-
Journal article (peer-reviewed)abstract
- Complex oxides show extreme sensitivity to structural distortions and defects, and the intricate balance of competing interactions which emerge at atomically defined interfaces may give rise to unexpected physics. In the interfaces of non-magnetic complex oxides, one of the most intriguing properties is the emergence of magnetism which is sensitive to chemical defects. Particularly, it is unclear which defects are responsible for the emergent magnetic interfaces. Here, we show direct and clear experimental evidence, supported by theoretical explanation, that the B-site cation stoichiometry is crucial for the creation and control of magnetism at the interface between non-magnetic ABO3-perovskite oxides, LaAlO3 and SrTiO3. We find that consecutive defect formation, driven by atomic charge compensation, establishes the formation of robust perpendicular magnetic moments at the interface. Our observations propose a route to tune these emerging magnetoelectric structures, which are strongly coupled at the polar-nonpolar complex oxide interfaces.
|
|
| 9. |
- Wilson, Stephanie J., et al.
(author)
-
Global subterranean estuaries modify groundwater nutrient loading to the ocean
- 2024
-
In: Limnology And Oceanography Letters. - 2378-2242.
-
Journal article (peer-reviewed)abstract
- Terrestrial groundwater travels through subterranean estuaries before reaching the sea. Groundwater-derived nutrients drive coastal water quality, primary production, and eutrophication. We determined how dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), and dissolved organic nitrogen (DON) are transformed within subterranean estuaries and estimated submarine groundwater discharge (SGD) nutrient loads compiling > 10,000 groundwater samples from 216 sites worldwide. Nutrients exhibited complex, nonconservative behavior in subterranean estuaries. Fresh groundwater DIN and DIP are usually produced, and DON is consumed during transport. Median total SGD (saline and fresh) fluxes globally were 5.4, 2.6, and 0.18 Tmol yr−1 for DIN, DON, and DIP, respectively. Despite large natural variability, total SGD fluxes likely exceed global riverine nutrient export. Fresh SGD is a small source of new nutrients, but saline SGD is an important source of mostly recycled nutrients. Nutrients exported via SGD via subterranean estuaries are critical to coastal biogeochemistry and a significant nutrient source to the oceans.
|
|
| 10. |
- Eremeev, S. V., et al.
(author)
-
Insight into the electronic structure of the centrosymmetric skyrmion magnet GdRu 2 Si 2
- 2023
-
In: Nanoscale Advances. - 2516-0230. ; 5:23, s. 6678-6687
-
Journal article (peer-reviewed)abstract
- The discovery of a square magnetic-skyrmion lattice in GdRu2Si2, with the smallest so far found skyrmion size and without a geometrically frustrated lattice, has attracted significant attention. In this work, we present a comprehensive study of surface and bulk electronic structures of GdRu2Si2 by utilizing momentum-resolved photoemission (ARPES) measurements and first-principles calculations. We show how the electronic structure evolves during the antiferromagnetic transition when a peculiar helical order of 4f magnetic moments within the Gd layers sets in. A nice agreement of the ARPES-derived electronic structure with the calculated one has allowed us to characterize the features of the Fermi surface (FS), unveil the nested region along kz at the corner of the 3D FS, and reveal their orbital compositions. Our findings suggest that the Ruderman-Kittel-Kasuya-Yosida interaction plays a decisive role in stabilizing the spiral-like order of Gd 4f moments responsible for the skyrmion physics in GdRu2Si2. Our results provide a deeper understanding of electronic and magnetic properties of this material, which is crucial for predicting and developing novel skyrmion-based systems.
|
|
| 11. |
- Fedorov, A. V., et al.
(author)
-
Insight into the Temperature Evolution of Electronic Structure and Mechanism of Exchange Interaction in EuS
- 2021
-
In: Journal of Physical Chemistry Letters. - : American Chemical Society (ACS). - 1948-7185. ; 12:34, s. 8328-8334
-
Journal article (peer-reviewed)abstract
- Discovered in 1962, the divalent ferromagnetic semiconductor EuS (TC = 16.5 K, Eg = 1.65 eV) has remained constantly relevant to the engineering of novel magnetically active interfaces, heterostructures, and multilayer sequences and to combination with topological materials. Because detailed information on the electronic structure of EuS and, in particular, its evolution across TC is not well-represented in the literature but is essential for the development of new functional systems, the present work aims at filling this gap. Our angle-resolved photoemission measurements complemented with first-principles calculations demonstrate how the electronic structure of EuS evolves across a paramagnetic-ferromagnetic transition. Our results emphasize the importance of the strong Eu 4f-S 3p mixing for exchange-magnetic splittings of the sulfur-derived bands as well as coupling between f and d orbitals of neighboring Eu atoms to derive the value of TC accurately. The 4f-3p mixing facilitates the coupling between 4f and 5d orbitals of neighboring Eu atoms, which mainly governs the exchange interaction in EuS.
|
|
| 12. |
|
|
| 13. |
|
|
| 14. |
|
|
| 15. |
|
|
| 16. |
|
|
| 17. |
- Weilenmann, S., et al.
(author)
-
Health Care Workers’ Mental Health During the First Weeks of the SARS-CoV-2 Pandemic in Switzerland—A Cross-Sectional Study
- 2021
-
In: Frontiers in Psychiatry. - : Frontiers Media S.A.. - 1664-0640. ; 12
-
Journal article (peer-reviewed)abstract
- Objective: The current SARS-CoV-2 pandemic poses various challenges for health care workers (HCWs). This may affect their mental health, which is crucial to maintain high quality medical care during a pandemic. Existing evidence suggests that HCWs, especially women, nurses, frontline staff, and those exposed to COVID-19 patients, are at risk for anxiety and depression. However, a comprehensive overview of risk and protective factors considering their mutual influence is lacking. Therefore, this study aimed at exploring HCWs’ mental health during the SARS-CoV-2 pandemic in Switzerland, investigating the independent effect of various demographic, work- and COVID-related factors on HCWs’ mental health. Methods: In an exploratory, cross-sectional, nation-wide online survey, we assessed demographics, work characteristics, COVID-19 exposure, and anxiety, depression, and burnout in 1,406 HCWs during the beginning of the SARS-CoV-2 pandemic in Switzerland. Network analysis was used to investigate the associations among the included variables. Results: Women (compared to men), nurses (compared to physicians), frontline staff (compared to non-frontline workers), and HCWs exposed to COVID-19 patients (compared to non-exposed) reported more symptoms than their peers. However, these effects were all small. Perceived support by the employer independently predicted anxiety and burnout after adjustment for other risk factors. Conclusion: Our finding that some HCWs had elevated levels of anxiety, depression, and burnout underscores the importance to systematically monitor HCWs’ mental health during this ongoing pandemic. Because perceived support and mental health impairments were negatively related, we encourage the implementation of supportive measures for HCWs’ well-being during this crisis. © Copyright © 2021 Weilenmann, Ernst, Petry, Pfaltz, Sazpinar, Gehrke, Paolercio, von KÀnel and Spiller.
|
|
| 18. |
- Alexander, Gerianne, et al.
(author)
-
The sounds of science-a symphony for many instruments and voices
- 2020
-
In: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 95:6
-
Journal article (peer-reviewed)abstract
- Sounds of Science is the first movement of a symphony for many (scientific) instruments and voices, united in celebration of the frontiers of science and intended for a general audience. John Goodenough, the maestro who transformed energy usage and technology through the invention of the lithium-ion battery, opens the programme, reflecting on the ultimate limits of battery technology. This applied theme continues through the subsequent pieces on energy-related topics-the sodium-ion battery and artificial fuels, by Martin Mansson-and the ultimate challenge for 3D printing, the eventual production of life, by Anthony Atala. A passage by Gerianne Alexander follows, contemplating a related issue: How might an artificially produced human being behave? Next comes a consideration of consciousness and free will by Roland Allen and Suzy Lidstrom. Further voices and new instruments enter as Warwick Bowen, Nicolas Mauranyapin and Lars Madsen discuss whether dynamical processes of single molecules might be observed in their native state. The exploitation of chaos in science and technology, applications of Bose-Einstein condensates and the significance of entropy follow in pieces by Linda Reichl, Ernst Rasel and Roland Allen, respectively. Mikhail Katsnelson and Eugene Koonin then discuss the potential generalisation of thermodynamic concepts in the context of biological evolution. Entering with the music of the cosmos, Philip Yasskin discusses whether we might be able to observe torsion in the geometry of the Universe. The crescendo comes with the crisis of singularities, their nature and whether they can be resolved through quantum effects, in the composition of Alan Coley. The climax is Mario Krenn, Art Melvin and Anton Zeilinger's consideration of how computer code can be autonomously surprising and creative. In a harmonious counterpoint, his 'Guidelines for considering AIs as coauthors', Roman Yampolskiy concludes that code is not yet able to take responsibility for coauthoring a paper. An interlude summarises a speech by Zdenek Papousek. In a subsequent movement, new themes emerge as we seek to comprehend how far we have travelled along the path to understanding, and speculate on where new physics might arise. Who would have imagined, 100 years ago, a global society permeated by smartphones and scientific instruments so sophisticated that genes can be modified and gravitational waves detected?
|
|
| 19. |
|
|
| 20. |
- Bell, Brian, et al.
(author)
-
Sustainable Bridges – Past and Future. Reflections on a European Project 2003 – 2007
- 2023
-
In: IABSE Congress 2023 New Delhi, Engineering for Sustainable Development. - : International Association for Bridge and Structural Engineering. ; , s. 690-698
-
Conference paper (peer-reviewed)abstract
- Twenty years ago, in 2003, a European project was started to increase the sustainability of existing railway bridges. This paper summarises what was achieved and looks ahead. Nine Working Packages were organized: (1) Background material; (2) Guidance by stakeholders; (3) Condition Assessment and Inspection Guidelines; (4) Loads, Capacity and Resistance Guidelines; (5) Monitoring Guidelines; (6) Repair and Strengthening Guidelines; (7) Demonstration with Field testing of Bridges; (8) Demonstration on Monitoring on Bridges; and (9) Training and Dissemination.Some of the main results (from 4 Guidelines and 47 Background documents) are highlighted and some experiences, conclusions and thoughts about the future are given. Hidden strengths and weaknesses are discussed, analyses and codes for assessment can be improved, new monitoring and strengthening methods are available and life length can be prolonged.
|
|
| 21. |
- Bell, Brian, et al.
(author)
-
Sustainable Bridges - Past and Future Reflections on a European Project 2003-2007
- 2023
-
In: IABSE Congress, New Delhi 2023: Engineering for Sustainable Development, Report. ; , s. 690-698
-
Conference paper (peer-reviewed)abstract
- Twenty years ago, in 2003, a European project was started to increase the sustainability of existing railway bridges. This paper summarises what was achieved and looks ahead. Nine Working Packages were organized: (1) Background material; (2) Guidance by stakeholders; (3) Condition Assessment and Inspection Guidelines; (4) Loads, Capacity and Resistance Guidelines; (5) Monitoring Guidelines; (6) Repair and Strengthening Guidelines; (7) Demonstration with Field testing of Bridges; (8) Demonstration on Monitoring on Bridges; and (9) Training and Dissemination Some of the main results (from 4 Guidelines and 47 Background documents) are highlighted and some experiences, conclusions and thoughts about the future are given. Hidden strengths and weaknesses are discussed, analyses and codes for assessment can be improved, new monitoring and strengthening methods are available and life length can be prolonged.
|
|
| 22. |
- Ejbye-Ernst, Peter, et al.
(author)
-
"It's illegal to buy drugs from street dealers" : a video-based pre-post study of a behavioral intervention to displace dealers from an Amsterdam open-air drug market
- 2023
-
In: Journal of Experimental Criminology. - : Springer. - 1573-3750 .- 1572-8315.
-
Journal article (peer-reviewed)abstract
- Objectives: A high number of street dealers operate in the Red Light District in Amsterdam, The Netherlands. To displace the dealers, the Municipality of Amsterdam installed text-based light projections in a street attracting a high number of dealers.Methods: To evaluate the intervention, we did a pre-post analysis of video footage from two CCTV cameras located in the street. In total, we analyzed 765 one-minute segments of footage from before and after the implementation.Results: The implementation was followed by a four percentage point reduction in street dealers. However, the estimated effect shows fragileness with wide confidence intervals and a p-value just below 0.05, and a Bayesian robustness analysis suggests that the intervention was not associated with the outcome.Conclusions: Analyzing CCTV-footage offers a unique avenue for evaluating small scale interventions in open-air drug markets. While we observed a decrease in the presence of dealers, the intervention still needs further validation.
|
|
| 23. |
- Ernst, R. E., et al.
(author)
-
Identification of the ca. 720 Ma Irkutsk LIP and its plume centre in southern Siberia : The initiation of Laurentia-Siberia separation
- 2023
-
In: Precambrian Research. - 0301-9268. ; 394
-
Journal article (peer-reviewed)abstract
- Widespread 720 Ma magmatism has been linked with the break-up of Rodinia and the onset of the Sturtian ‘Snowball Earth’ event. We report a new U-Pb baddeleyite age from the Baikal dyke subswarm in southern Siberia which increases the known extent of the 720 Ma Irkutsk LIP and confirms a previous hypothesis that the Baikal and Sayan subswarms converge at the southern tip of the Irkutsk promontory. Together they define a mantle plume centre with direct links to the 720 Ma Franklin plume centre of northern Laurentia, thus constraining the paleo-reconstruction of southern Siberia and northern Laurentia. It is inferred that this combined 720 Franklin – Irktusk LIP event is associated with the breakup of southern Siberia from northern Laurentia during fragmentation of the Rodinia supercontinent. Expansion of 720 Ma magmatism into Siberia greatly increases the scale of the Franklin-Irktusk LIP.
|
|
| 24. |
- Ernst, Stefan, et al.
(author)
-
Legionella effector AnkX displaces the switch II region for Rab1b phosphocholination
- 2020
-
In: Science Advances. - : American Association for the Advancement of Science. - 2375-2548. ; 6:20
-
Journal article (peer-reviewed)abstract
- The causative agent of Legionnaires disease, Legionella pneumophila, translocates the phosphocholine transferase AnkX during infection and thereby posttranslationally modifies the small guanosine triphosphatase (GTPase) Rab1 with a phosphocholine moiety at S76 using cytidine diphosphate (CDP)–choline as a cosubstrate. The molecular basis for Rab1 binding and enzymatic modification have remained elusive because of lack of structural information of the low-affinity complex with AnkX. We combined thiol-reactive CDP-choline derivatives with recombinantly introduced cysteines in the AnkX active site to covalently capture the heterocomplex. The resulting crystal structure revealed that AnkX induces displacement of important regulatory elements of Rab1 by placing a β sheet into a conserved hydrophobic pocket, thereby permitting phosphocholine transfer to the active and inactive states of the GTPase. Together, the combination of chemical biology and structural analysis reveals the enzymatic mechanism of AnkX and the family of filamentation induced by cyclic adenosine monophosphate (FIC) proteins.
|
|
| 25. |
- Ernst, Yolandi, et al.
(author)
-
The African Regional Greenhouse Gases Budget (2010–2019)
- 2024
-
In: Global Biogeochemical Cycles. - 0886-6236. ; 38:4
-
Journal article (peer-reviewed)abstract
- As part of the REgional Carbon Cycle Assessment and Processes Phase 2 (RECCAP2) project, we developed a comprehensive African Greenhouse gases (GHG) budget covering 2000 to 2019 (RECCAP1 and RECCAP2 time periods), and assessed uncertainties and trends over time. We compared bottom-up process-based models, data-driven remotely sensed products, and national GHG inventories with top-down atmospheric inversions, accounting also for lateral fluxes. We incorporated emission estimates derived from novel methodologies for termites, herbivores, and fire, which are particularly important in Africa. We further constrained global woody biomass change products with high-quality regional observations. During the RECCAP2 period, Africa's carbon sink capacity is decreasing, with net ecosystem exchange switching from a small sink of −0.61 ± 0.58 PgC yr−1 in RECCAP1 to a small source in RECCAP2 at 0.16 (−0.52/1.36) PgC yr−1. Net CO2 emissions estimated from bottom-up approaches were 1.6 (−0.9/5.8) PgCO2 yr−1, net CH4 were 77 (56.4/93.9) TgCH4 yr−1 and net N2O were 2.9 (1.4/4.9) TgN2O yr−1. Top-down atmospheric inversions showed similar trends. Land Use Change emissions increased, representing one of the largest contributions at 1.7 (0.8/2.7) PgCO2eq yr−1 to the African GHG budget and almost similar to emissions from fossil fuels at 1.74 (1.53/1.96) PgCO2eq yr−1, which also increased from RECCAP1. Additionally, wildfire emissions decreased, while fuelwood burning increased. For most component fluxes, uncertainty is large, highlighting the need for increased efforts to address Africa-specific data gaps. However, for RECCAP2, we improved our overall understanding of many of the important components of the African GHG budget that will assist to inform climate policy and action.
|
|
