| 1. |
- Botvinik-Nezer, Rotem, et al.
(författare)
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Variability in the analysis of a single neuroimaging dataset by many teams
- 2020
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 582, s. 84-88
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Tidskriftsartikel (refereegranskat)abstract
- Data analysis workflows in many scientific domains have become increasingly complex and flexible. Here we assess the effect of this flexibility on the results of functional magnetic resonance imaging by asking 70 independent teams to analyse the same dataset, testing the same 9 ex-ante hypotheses(1). The flexibility of analytical approaches is exemplified by the fact that no two teams chose identical workflows to analyse the data. This flexibility resulted in sizeable variation in the results of hypothesis tests, even for teams whose statistical maps were highly correlated at intermediate stages of the analysis pipeline. Variation in reported results was related to several aspects of analysis methodology. Notably, a meta-analytical approach that aggregated information across teams yielded a significant consensus in activated regions. Furthermore, prediction markets of researchers in the field revealed an overestimation of the likelihood of significant findings, even by researchers with direct knowledge of the dataset(2-5). Our findings show that analytical flexibility can have substantial effects on scientific conclusions, and identify factors that may be related to variability in the analysis of functional magnetic resonance imaging. The results emphasize the importance of validating and sharing complex analysis workflows, and demonstrate the need for performing and reporting multiple analyses of the same data. Potential approaches that could be used to mitigate issues related to analytical variability are discussed. The results obtained by seventy different teams analysing the same functional magnetic resonance imaging dataset show substantial variation, highlighting the influence of analytical choices and the importance of sharing workflows publicly and performing multiple analyses.
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| 2. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 3. |
- Arzoumanian, Doris, et al.
(författare)
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Dust polarized emission observations of NGC 6334: BISTRO reveals the details of the complex but organized magnetic field structure of the high-mass star-forming hub-filament network
- 2021
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 647
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Tidskriftsartikel (refereegranskat)abstract
- Context. Molecular filaments and hubs have received special attention recently thanks to new studies showing their key role in star formation. While the (column) density and velocity structures of both filaments and hubs have been carefully studied, their magnetic field (B-field) properties have yet to be characterized. Consequently, the role of B-fields in the formation and evolution of hub-filament systems is not well constrained. Aims. We aim to understand the role of the B-field and its interplay with turbulence and gravity in the dynamical evolution of the NGC 6334 filament network that harbours cluster-forming hubs and high-mass star formation. Methods. We present new observations of the dust polarized emission at 850 μm toward the 2 pc × 10 pc map of NGC 6334 at a spatial resolution of 0.09 pc obtained with the James Clerk Maxwell Telescope (JCMT) as part of the B-field In STar-forming Region Observations (BISTRO) survey. We study the distribution and dispersion of the polarized intensity (PI), the polarization fraction (PF), and the plane-of-The-sky B-field angle (χB_POS) toward the whole region, along the 10 pc-long ridge and along the sub-filaments connected to the ridge and the hubs. We derived the power spectra of the intensity and χBPOS along the ridge crest and compared them with the results obtained from simulated filaments. Results. The observations span 3 orders of magnitude in Stokes I and PI and 2 orders of magnitude in PF (from 0.2 to 20%). A large scatter in PI and PF is observed for a given value of I. Our analyses show a complex B-field structure when observed over the whole region ( 10 pc); however, at smaller scales (1 pc), χBPOS varies coherently along the crests of the filament network. The observed power spectrum of χBPOS can be well represented with a power law function with a slope of-1.33 ± 0.23, which is 20% shallower than that of I. We find that this result is compatible with the properties of simulated filaments and may indicate the physical processes at play in the formation and evolution of star-forming filaments. Along the sub-filaments, χBPOS rotates frombeing mostly perpendicular or randomly oriented with respect to the crests to mostly parallel as the sub-filaments merge with the ridge and hubs. This variation of the B-field structure along the sub-filaments may be tracing local velocity flows of infalling matter in the ridge and hubs. Our analysis also suggests a variation in the energy balance along the crests of these sub-filaments, from magnetically critical or supercritical at their far ends to magnetically subcritical near the ridge and hubs. We also detect an increase in PF toward the high-column density (NH2 â 1023 cm-2) star cluster-forming hubs. These latter large PF values may be explained by the increase in grain alignment efficiency due to stellar radiation from the newborn stars, combined with an ordered B-field structure. Conclusions. These observational results reveal for the first time the characteristics of the small-scale (down to 0.1 pc) B-field structure of a 10 pc-long hub-filament system. Our analyses show variations in the polarization properties along the sub-filaments that may be tracing the evolution of their physical properties during their interaction with the ridge and hubs. We also detect an impact of feedback from young high-mass stars on the local B-field structure and the polarization properties, which could put constraints on possible models for dust grain alignment and provide important hints as to the interplay between the star formation activity and interstellar B-fields.
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| 4. |
- Blencowe, Hannah, et al.
(författare)
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Stillbirth outcome capture and classification in population-based surveys : EN-INDEPTH study
- 2021
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Ingår i: Population Health Metrics. - : BioMed Central (BMC). - 1478-7954. ; 19
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Tidskriftsartikel (refereegranskat)abstract
- Background: Household surveys remain important sources of stillbirth data, but omission and misclassification are common. Classifying adverse pregnancy outcomes as stillbirths requires accurate reporting of vital status at birth and gestational age or birthweight for every pregnancy. Further categorisation, e.g. by sex, or timing (intrapartum/antepartum) improves data to understand and prevent stillbirth.Methods: We undertook a cross-sectional population-based survey of women of reproductive age in five health and demographic surveillance system sites in Bangladesh, Ethiopia, Ghana, Guinea-Bissau and Uganda (2017-2018). All women answered a full birth history with pregnancy loss questions (FBH+) or a full pregnancy history (FPH). A sub-sample across both groups were asked additional stillbirth questions. Questions were evaluated using descriptive measures. Using an interpretative paradigm and phenomenology methodology, focus group discussions with women exploring barriers to reporting birthweight for stillbirths were conducted. Thematic analysis was guided by an a priori codebook.Results: Overall 69,176 women reported 98,483 livebirths (FBH+) and 102,873 pregnancies (FPH). Additional questions were asked for 1453 stillbirths, 1528 neonatal deaths and 12,620 surviving children born in the 5years prior to the survey. Completeness was high (> 99%) for existing FBH+/FPH questions on signs of life at birth and gestational age (months). Discordant responses in signs of life at birth between different questions were common; nearly one-quarter classified as stillbirths on FBH+/FPH were reported born alive on additional questions. Availability of information on gestational age (weeks) (58.1%) and birthweight (13.2%) was low amongst stillbirths, and heaping was common. Most women (93.9%) were able to report the sex of their stillborn baby. Response completeness for stillbirth timing (18.3-95.1%) and estimated proportion intrapartum (15.6-90.0%) varied by question and site. Congenital malformations were reported in 3.1% stillbirths. Perceived value in weighing a stillborn baby varied and barriers to weighing at birth a nd knowing birthweight were common.Conclusions: Improving stillbirth data in surveys will require investment in improving the measurement of vital status, gestational age and birthweight by healthcare providers, communication of these with women, and overcoming reporting barriers. Given the large burden and effect on families, improved data must be made available to end preventable stillbirths.
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| 5. |
- Carson, Doris A., et al.
(författare)
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Cities, hinterlands and disconnected urban-rural development : Perspectives from sparsely populated areas
- 2022
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Ingår i: Journal of Rural Studies. - : Elsevier. - 0743-0167 .- 1873-1392. ; 93, s. 104-111
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Tidskriftsartikel (refereegranskat)abstract
- This article introduces the special issue ‘Rural hinterland development in sparsely populated areas (SPAs): new challenges and opportunities arising from urbanisation within the periphery’. It problematises the relationships between growing cities and hinterland areas in SPAs, such as those commonly found in Arctic, Outback and similar remote resource peripheries of developed countries. Many SPAs are rapidly urbanising, with polarised development becoming an ever-increasing concern for regional planners and policy-makers. This special issue contributes to debates about the impact that urban growth and city-centric development strategies in SPAs might have on the development prospects for small and distant settlements in the hinterland. We first discuss why SPAs are different from other rural contexts when it comes to urban-rural interactions and introduce the idea of regional disconnectedness as a defining feature of SPAs. We then review the papers in this collection, which include perspectives from northern Sweden, Iceland, Finland, Scotland, Alaska, and Australia, and position them according to their contributions to theory, policy and practice. The special issue challenges assumptions that city-centric regional development in SPAs will automatically generate spillover or backwash effects for the hinterland. It emphasises the need to consider diverse mobility flows within SPAs as part of urban-rural interactions. It also raises attention to micro-scale urbanisation within the hinterland, with housing, services, and amenities increasingly concentrating in a few small towns. The final discussion outlines important areas for research into more effective urban-rural partnership building in SPAs and on how to embrace regional disconnectedness for more targeted hinterland development.
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| 6. |
- Carson, Doris A., et al.
(författare)
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Northern cities and urban–rural migration of university-qualified labour in Australia and Sweden : Spillovers, sponges, or disconnected city–hinterland geographies?
- 2021
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Ingår i: Geographical Research. - : John Wiley & Sons. - 1745-5863 .- 1745-5871. ; 59:3, s. 424-438
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Tidskriftsartikel (refereegranskat)abstract
- This article examines the migration flows of university-qualified labour (UQL) between cities and hinterland regions in the sparsely populated north of both Australia and Sweden. These peripheries have become increasingly urbanised in recent decades and have received substantial investment in urban higher education hubs that are expected to generate skills for their regions. Whether these skills remain within the few urban centres or are redistributed internally to benefit rural and remote locations is not known. The article identifies the extent to which there have been urban–rural ‘spillover’ or ‘sponge’ effects in UQL migration flows within the north and establishes whether there has been a ‘disconnect’ in the regional exchange of UQL. Drawing on recent Australian census and Swedish register data, the results suggest that ‘spillover’ and ‘sponging’ of UQL have been limited, particularly in Northern Australia where cities appeared quite disconnected from their hinterlands. Spillover was more common in Northern Sweden, but cities with universities targeting regional skill needs did not necessarily generate more net-migration gains for their hinterland. The discussion illustrates why urban–rural human capital relationships in northern peripheries may be more diverse and complex than assumed and flags what policy lessons can be drawn from comparing different northern peripheries.
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| 7. |
- Carson, Doris A., et al.
(författare)
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Opportunities and barriers for degrowth in remote tourism destinations : overcoming regional inequalities?
- 2021
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Ingår i: Degrowth and tourism. - Milton Park : Routledge. - 9780367335656 - 9780429320590 ; , s. 100-115
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Bokkapitel (refereegranskat)abstract
- This chapter examines the opportunities and barriers for de-growth to be used in future tourism development strategies for remote or peripheral destinations, illustrated by the case of the Top End region in the Northern Territory of Australia. In such remote contexts, tourism has often evolved around an entrenched boosterist growth paradigm, a dependence on export markets and external investors, a susceptibility to 'boom and bust' cycles, and increasing spatial and social inequalities between the dominant urban growth centre and a declining sparsely populated hinterland. The chapter discusses how de-growth may help in reducing the city-hinterland development gap by directing attention to the benefits of alternative niche markets, the regional dispersal of tourists, smaller-scale and dispersed infrastructure and product investment, a re-positioning of tourism as part of broader community development agendas, and renewed efforts to encourage local involvement in decision-making. The chapter also considers the institutional barriers to such an approach, and considers why it may remain an unrealistic concept for remote political economies that are increasingly confronted with recurring periods of economic crisis and highly volatile industries and populations.
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| 8. |
- Carson, Dean B., 1970-, et al.
(författare)
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Disruptions and diversions : the demographic consequences of natural disasters in sparsely populated areas
- 2021
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Ingår i: The demography of disasters. - Cham : Springer. - 9783030499198 - 9783030499204 ; , s. 81-99
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Bokkapitel (refereegranskat)abstract
- The Eight Ds model (Carson and Carson 2014) explains the unique characteristics of human and economic geography for sparsely populated areas (SPAs) as disconnected, discontinuous, diverse, detailed, dynamic, distant, dependent and delicate. According to the model, SPAs are subject to dramatic changes in demographic characteristics that result from both identifiable black swan events and less apparent tipping points in longer-term processes of demographic change (Carson et al. 2011). The conceptual foundations for this assertion are clear. Populations in SPAs can experience large and long-term impacts on the overall demographic structureas a result of decisions by a relatively small number of people. High levels of migration and mobility cause constant shifts in the demographic profile and prime SPAs to adapt to many different demographic states (Carson and Carson 2014). The Northern Territory of Australia, for example, experienced previously unseen waves of pre-retirement aged migrants in the past decade or so (Martel et al. 2013) as evidence of detailed but important changes to past trends. However, while dramatic demographic changes are conceptually possible and occasionally observable, there have been few attempts to examine the conditions under which such changes are likely to occur or not to occur. This is an important question particularly in relation to black swan events such as natural disasters because effective disaster management policy and planning is at least partially dependent on understanding who is affected and in what ways (Bird et al. 2013). The purpose of this chapter, therefore, is to begin the process of identifying the conditions under which dramatic demographic responses to natural disasters in SPAs might occur. In the process, we introduce two new 'Ds' with which to describe the nature of demographic change. We propose that natural disasters such as cyclones, floods, earthquakes, bushfires, landslides, avalanches and crop failures present the potential to disrupt or to divert demographic development.
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| 9. |
- Carson, Dean B., 1970-, et al.
(författare)
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Resource deserts, village hierarchies and de-growth in sparsely populated areas : The case of Southern Lapland, Sweden
- 2022
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Ingår i: Fennia. - : Geographical Society of Finland. - 1798-5617. ; 200:2, s. 210-227
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Tidskriftsartikel (refereegranskat)abstract
- Small villages in northern Sweden have seen a continuing removal of key services, such as schools, shops and public transport, since the 1970s. Disinvestment in public services has not been strategically planned but has happened in response to population loss and increased costs on a case-by-case basis. More recently, there has been a shift in policy thinking to what might be termed a ‘de-growth’ approach where digitalisation and increased personal mobility are used to provide new ways of delivering services. The purpose of this paper is to examine the existence of ‘resource deserts’ in Southern Lapland and the emergence (or consolidation) of village hierarchies in allocating public services. We map out the distribution of neighbourhood services (grocery stores, pre-/schools and petrol pumps) among villages, and explore the lived experiences in accessing these resources in different villages. Our results show that resource deserts clearly exist in the south and east of the region, while villages in the more sparsely populated western mountain areas were generally in a better position to retain resources. We identify a lack of consistent and transparent service planning at the village level as a key shortcoming in municipal and regional service strategies. There appear to be unofficial settlement hierarchies in the differential treatment of villages that are otherwise similar in population size, population change and distance to central places. We find that political decisions on service allocations are likely influenced by several factors. These include legacy effects relating to historic settlement status, the location of villages in relation to key transport or mobility corridors, as well as ideological factors favouring villages with more ‘exotic’ features and development potential in line with the municipalities’ economic, social and political priorities. We finally argue that a shift to de-growth needs to be more strategically planned if it is to eliminate resource deserts and promote equity of service access across all villages.
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| 10. |
- Carson, Dean B., et al.
(författare)
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Small villages and socio-economic change in resource peripheries : a view from Northern Sweden
- 2020
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Ingår i: Dipping in to the North. - Singapore : Palgrave Macmillan. - 9789811566226 - 9789811566233 ; , s. 27-53
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Bokkapitel (refereegranskat)abstract
- Many towns and villages in the inland north of Sweden were settled by independent farmers and foresters, with industry and company towns being relatively rare. In Canada and Australia industry and company towns were more common, and there is some evidence that those towns have found it more difficult to attract and retain population than what we term here as 'settler towns'. Development of alternative economic activities such as tourism has been difficult. In Sweden, however, there is no clear distinction between the recent demographic performance of industry and settler villages, and local economic activity has been relatively unimportant as most villages are well connected to regional labour markets.
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| 11. |
- Carson, Dean B., 1970-, et al.
(författare)
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The mining resource cycle and settlement demography in Malå, Northern Sweden
- 2020
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Ingår i: Polar Record. - : Cambridge University Press. - 0032-2474 .- 1475-3057. ; 56
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Tidskriftsartikel (refereegranskat)abstract
- Research on the demographic impacts of mining in sparsely populated areas has focused primarily on relatively large towns. Less attention has been paid to smaller villages, which may experience different impacts because of their highly concentrated economies and their small populations, making them more vulnerable to demographic “boom and bust” effects. This paper examines demographic change in four small villages in northern Sweden, which are located close to several mining projects but have evolved through different degrees of integration with or separation from mining. Using a longitudinal “resource cycle” perspective, the demographic trajectories of the villages are compared to understand how different types of settlement and engagement with mining have led to different demographic outcomes in the long term. While the four villages experienced similar trajectories in terms of overall population growth and decline, their experiences in relation to more nuanced indicators, including age and gender distributions and population mobilities, were different, and potential reasons for this are discussed. Due to data limitations, however, the long-term demographic consequences of mining for local Sami people remain unclear. The paper problematises this research gap in light of general concerns about mining impacts on traditional Sami livelihoods.
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| 12. |
- Carson, Dean B., 1970-, et al.
(författare)
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Understanding the demographic future of small Arctic villages using agent-based modelling
- 2022
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Ingår i: More than 'nature'. - Vienna : LIT Verlag. - 9783643912183 - 9783643962188 ; , s. 263-281
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Bokkapitel (refereegranskat)abstract
- Large parts of the Scandinavian Arctic and sub-Arctic are characterized by small settlements of just a few dozen or hundred inhabitants. Many of these villages have experienced loss of population and services. However, recent in-migration and new technologies facilitating ageing in place and e-commute work have seen some villages grow, some stabilize their population base, and many undergo dramatic demographic transformation. These local processes have largely been hidden from policy-makers and planners because standard statistical analyses and demographic modeling are either only applied at regional level, or are poorly suited to such small populations. This chapter introduces an agent-based demographic model (ABDM) applied to small villages in the north of Sweden. ABDMs provide a way to combine quantitative and qualitative data about demographic change processes and model the impacts of these on population size, structure, and dynamics over time. This chapter presents examples of how ABDMs provide insights into demographic change in the northern inland of Sweden and how they might facilitate truly local-level planning in a peripheral Arctic context.
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| 13. |
- Carson, Dean B., 1970-, et al.
(författare)
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Who gives? Non-commercial distribution networks in domestic food production in the inland north of Sweden
- 2024
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Ingår i: Sustainability. - : MDPI. - 2071-1050. ; 16:6
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Tidskriftsartikel (refereegranskat)abstract
- This paper examines the social context of “domestic food production” (dfp) in the inland North of Sweden, with a focus on understanding the contributions of non-commercial food distribution to local food security and sustainable rural community-building. We report on the findings of an exploratory pilot study that included an online survey of 305 people who engaged in at least one dfp activity (hunting, fishing, foraging, or farming). The aims were to uncover common social practices of dfp, as well as to identify key values attached to dfp, the extent of commercial and non-commercial distribution of home-produced food, and motivations to give away food. The main findings emphasize the social nature of dfp activities, with the vast majority of respondents undertaking dfp in groups or as part of formal clubs. Key values attached to dfp included social and community-related aspects, while commercial interests were limited. Respondents were more likely to engage in non-commercial distribution networks, usually involving close family and friends. Food givers mostly cited social factors as their main motivations rather than other food-related aspects (such as food security, health benefits, or food waste). Food givers were also likely to receive food from others, emphasizing the relatively narrow and reciprocal character of non-commercial food networks. We conclude that non-commercial dfp networks may be expanded to the broader community by exploiting the social nature of dfp and encouraging generalized reciprocity led by dfp clubs. This could potentially reduce the negative impacts of food deserts whilst also stimulating community interactions, learning and local dfp communities of practice.
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| 14. |
- Doi, Yasuo, et al.
(författare)
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The JCMT BISTRO Survey: Magnetic Fields Associated with a Network of Filaments in NGC 1333
- 2020
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 1538-4357 .- 0004-637X. ; 899:1
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Tidskriftsartikel (refereegranskat)abstract
- We present new observations of the active star formation region NGC 1333 in the Perseus molecular cloud complex from the James Clerk Maxwell Telescope B-Fields In Star-forming Region Observations (BISTRO) survey with the POL-2 instrument. The BISTRO data cover the entire NGC 1333 complex (∼1.5 pc ? 2 pc) at 0.02 pc resolution and spatially resolve the polarized emission from individual filamentary structures for the first time. The inferred magnetic field structure is complex as a whole, with each individual filament aligned at different position angles relative to the local field orientation. We combine the BISTRO data with low- and high- resolution data derived from Planck and interferometers to study the multiscale magnetic field structure in this region. The magnetic field morphology drastically changes below a scale of ∼1 pc and remains continuous from the scales of filaments (∼0.1 pc) to that of protostellar envelopes (∼0.005 pc or ∼1000 au). Finally, we construct simple models in which we assume that the magnetic field is always perpendicular to the long axis of the filaments. We demonstrate that the observed variation of the relative orientation between the filament axes and the magnetic field angles are well reproduced by this model, taking into account the projection effects of the magnetic field and filaments relative to the plane of the sky. These projection effects may explain the apparent complexity of the magnetic field structure observed at the resolution of BISTRO data toward the filament network.
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| 15. |
- Eswaraiah, Chakali, et al.
(författare)
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The JCMT BISTRO Survey: Revealing the Diverse Magnetic Field Morphologies in Taurus Dense Cores with Sensitive Submillimeter Polarimetry
- 2021
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Ingår i: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 912:2
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Tidskriftsartikel (refereegranskat)abstract
- We have obtained sensitive dust continuum polarization observations at 850 μm in the B213 region of Taurus using POL-2 on SCUBA-2 at the James Clerk Maxwell Telescope as part of the B-fields in STar-forming Region Observations (BISTRO) survey. These observations allow us to probe magnetic field (B-field) at high spatial resolution (∼2000 au or ∼0.01 pc at 140 pc) in two protostellar cores (K04166 and K04169) and one prestellar core (Miz-8b) that lie within the B213 filament. Using the Davis-Chandrasekhar-Fermi method, we estimate the B-field strengths in K04166, K04169, and Miz-8b to be 38 ± 14, 44 ± 16, and 12 ± 5 μG, respectively. These cores show distinct mean B-field orientations. The B-field in K04166 is well ordered and aligned parallel to the orientations of the core minor axis, outflows, core rotation axis, and large-scale uniform B-field, in accordance with magnetically regulated star formation via ambipolar diffusion taking place in K04166. The B-field in K04169 is found to be ordered but oriented nearly perpendicular to the core minor axis and large-scale B-field and not well correlated with other axes. In contrast, Miz-8b exhibits a disordered B-field that shows no preferred alignment with the core minor axis or large-scale field. We found that only one core, K04166, retains a memory of the large-scale uniform B-field. The other two cores, K04169 and Miz-8b, are decoupled from the large-scale field. Such a complex B-field configuration could be caused by gas inflow onto the filament, even in the presence of a substantial magnetic flux.
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| 16. |
- Hwang, Jihye, et al.
(författare)
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The JCMT BISTRO Survey: A Spiral Magnetic Field in a Hub-filament Structure, Monoceros R2
- 2022
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 1538-4357 .- 0004-637X. ; 941:1
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Tidskriftsartikel (refereegranskat)abstract
- We present and analyze observations of polarized dust emission at 850 μm toward the central 1 × 1 pc hub-filament structure of Monoceros R2 (Mon R2). The data are obtained with SCUBA-2/POL-2 on the James Clerk Maxwell Telescope (JCMT) as part of the B-fields in Star-forming Region Observations survey. The orientations of the magnetic field follow the spiral structure of Mon R2, which are well described by an axisymmetric magnetic field model. We estimate the turbulent component of the magnetic field using the angle difference between our observations and the best-fit model of the underlying large-scale mean magnetic field. This estimate is used to calculate the magnetic field strength using the Davis–Chandrasekhar–Fermi method, for which we also obtain the distribution of volume density and velocity dispersion using a column density map derived from Herschel data and the C18O (J = 3 - 2) data taken with HARP on the JCMT, respectively. We make maps of magnetic field strengths and mass-to-flux ratios, finding that magnetic field strengths vary from 0.02 to 3.64 mG with a mean value of 1.0 ± 0.06 mG, and the mean critical mass-to-flux ratio is 0.47 ± 0.02. Additionally, the mean Alfvén Mach number is 0.35 ± 0.01. This suggests that, in Mon R2, the magnetic fields provide resistance against large-scale gravitational collapse, and the magnetic pressure exceeds the turbulent pressure. We also investigate the properties of each filament in Mon R2. Most of the filaments are aligned along the magnetic field direction and are magnetically subcritical.
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| 17. |
- Häggström, Ida, 1982, et al.
(författare)
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Deep learning for [ 18 F]fluorodeoxyglucose-PET-CT classification in patients with lymphoma: a dual-centre retrospective analysis
- 2024
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Ingår i: The Lancet Digital Health. - 2589-7500. ; 6:2, s. e114-e125
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Tidskriftsartikel (refereegranskat)abstract
- Background : The rising global cancer burden has led to an increasing demand for imaging tests such as [18F]fluorodeoxyglucose ([18F]FDG)-PET-CT. To aid imaging specialists in dealing with high scan volumes, we aimed to train a deep learning artificial intelligence algorithm to classify [18F]FDG-PET-CT scans of patients with lymphoma with or without hypermetabolic tumour sites. Methods : In this retrospective analysis we collected 16 583 [18F]FDG-PET-CTs of 5072 patients with lymphoma who had undergone PET-CT before or after treatment at the Memorial Sloa Kettering Cancer Center, New York, NY, USA. Using maximum intensity projection (MIP), three dimensional (3D) PET, and 3D CT data, our ResNet34-based deep learning model (Lymphoma Artificial Reader System [LARS]) for [18F]FDG-PET-CT binary classification (Deauville 1–3 vs 4–5), was trained on 80% of the dataset, and tested on 20% of this dataset. For external testing, 1000 [18F]FDG-PET-CTs were obtained from a second centre (Medical University of Vienna, Vienna, Austria). Seven model variants were evaluated, including MIP-based LARS-avg (optimised for accuracy) and LARS-max (optimised for sensitivity), and 3D PET-CT-based LARS-ptct. Following expert curation, areas under the curve (AUCs), accuracies, sensitivities, and specificities were calculated. Findings : In the internal test cohort (3325 PET-CTs, 1012 patients), LARS-avg achieved an AUC of 0·949 (95% CI 0·942–0·956), accuracy of 0·890 (0·879–0·901), sensitivity of 0·868 (0·851–0·885), and specificity of 0·913 (0·899–0·925); LARS-max achieved an AUC of 0·949 (0·942–0·956), accuracy of 0·868 (0·858–0·879), sensitivity of 0·909 (0·896–0·924), and specificity of 0·826 (0·808–0·843); and LARS-ptct achieved an AUC of 0·939 (0·930–0·948), accuracy of 0·875 (0·864–0·887), sensitivity of 0·836 (0·817–0·855), and specificity of 0·915 (0·901–0·927). In the external test cohort (1000 PET-CTs, 503 patients), LARS-avg achieved an AUC of 0·953 (0·938–0·966), accuracy of 0·907 (0·888–0·925), sensitivity of 0·874 (0·843–0·904), and specificity of 0·949 (0·921–0·960); LARS-max achieved an AUC of 0·952 (0·937–0·965), accuracy of 0·898 (0·878–0·916), sensitivity of 0·899 (0·871–0·926), and specificity of 0·897 (0·871–0·922); and LARS-ptct achieved an AUC of 0·932 (0·915–0·948), accuracy of 0·870 (0·850–0·891), sensitivity of 0·827 (0·793–0·863), and specificity of 0·913 (0·889–0·937). Interpretation : Deep learning accurately distinguishes between [18F]FDG-PET-CT scans of lymphoma patients with and without hypermetabolic tumour sites. Deep learning might therefore be potentially useful to rule out the presence of metabolically active disease in such patients, or serve as a second reader or decision support tool. Funding: National Institutes of Health-National Cancer Institute Cancer Center Support Grant.
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| 18. |
- Knudsen, Gitte M, et al.
(författare)
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Guidelines for the content and format of PET brain data in publications and archives : A consensus paper
- 2020
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Ingår i: Journal of Cerebral Blood Flow and Metabolism. - : SAGE Publications. - 0271-678X .- 1559-7016. ; 40:8, s. 1576-1585
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Tidskriftsartikel (refereegranskat)abstract
- It is a growing concern that outcomes of neuroimaging studies often cannot be replicated. To counteract this, the magnetic resonance (MR) neuroimaging community has promoted acquisition standards and created data sharing platforms, based on a consensus on how to organize and share MR neuroimaging data. Here, we take a similar approach to positron emission tomography (PET) data. To facilitate comparison of findings across studies, we first recommend publication standards for tracer characteristics, image acquisition, image preprocessing, and outcome estimation for PET neuroimaging data. The co-authors of this paper, representing more than 25 PET centers worldwide, voted to classify information as mandatory, recommended, or optional. Second, we describe a framework to facilitate data archiving and data sharing within and across centers. Because of the high cost of PET neuroimaging studies, sample sizes tend to be small and relatively few sites worldwide have the required multidisciplinary expertise to properly conduct and analyze PET studies. Data sharing will make it easier to combine datasets from different centers to achieve larger sample sizes and stronger statistical power to test hypotheses. The combining of datasets from different centers may be enhanced by adoption of a common set of best practices in data acquisition and analysis.
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| 19. |
- Kwesiga, Doris, et al.
(författare)
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Adverse pregnancy outcome disclosure and women's social networks : a qualitative multi-country study with implications for improved reporting in surveys
- 2022
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Ingår i: BMC Pregnancy and Childbirth. - : BioMed Central (BMC). - 1471-2393 .- 1471-2393. ; 22:1
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundGlobally, approximately 6,700 newborn deaths and 5,400 stillbirths occur daily. The true figure is likely higher, with under reporting of adverse pregnancy outcomes (APOs) noted. Decision-making in health is influenced by various factors, including one's social networks. We sought to understand APOs disclosure within social networks in Uganda, Ghana, Guinea-Bissau and Bangladesh and how this could improve formal reporting of APOs in surveys.MethodsA qualitative, exploratory multi-country study was conducted within four health and demographic surveillance system sites. 16 focus group discussions were held with 147 women aged 15-49 years, who had participated in a recent household survey. Thematic analysis, with both deductive and inductive elements, using three pre-defined themes of Sender, Message and Receiver was done using NVivo software.ResultsDisclosure of APOs was a community concern, with news often shared with people around the bereaved for different reasons, including making sense of what happened and decision-making roles of receivers. Social networks responded with comfort, providing emotional, in-kind and financial support. Key decision makers included men, spiritual and traditional leaders. Non-disclosure was usually to avoid rumors in cases of induced abortions, or after a previous bad experience with health workers, who were frequently excluded from disclosure, except for instances where a woman sought advice on APOs.ConclusionsCommunities must understand why they should report APOs and to whom. Efforts to improve APOs reporting could be guided by diffusion of innovation theory, for instance for community entry and sensitization before the survey, since it highlights how information can be disseminated through community role models. In this case, these gatekeepers we identified could promote reporting of APOs. The stage at which a person is in decision-making, what kind of adopter they are and their take on the benefits and other attributes of reporting are important. In moving beyond survey reporting to getting better routine data, the theory would be applicable too. Health workers should demonstrate a more comforting and supportive response to APOs as the social networks do, which could encourage more bereaved women to inform them and seek care.
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| 20. |
- Kwesiga, Doris, et al.
(författare)
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Barriers and enablers to reporting pregnancy and adverse pregnancy outcomes in population-based surveys : EN-INDEPTH study
- 2021
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Ingår i: Population Health Metrics. - : BioMed Central (BMC). - 1478-7954. ; 19
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Tidskriftsartikel (refereegranskat)abstract
- Background: Risks of neonatal death, stillbirth and miscarriage are highest in low- and middle-income countries (LMICs), where data has most gaps and estimates rely on household surveys, dependent on women reporting these events. Underreporting of pregnancy and adverse pregnancy outcomes (APOs) is common, but few studies have investigated barriers to reporting these in LMICs. The EN-INDEPTH multi-country study applied qualitative approaches to explore barriers and enablers to reporting pregnancy and APOs in surveys, including individual, community, cultural and interview level factors.Methods: The study was conducted in five Health and Demographic Surveillance System sites in Guinea-Bissau, Ethiopia, Uganda, Bangladesh and Ghana. Using an interpretative paradigm and phenomenology methodology, 28 focus group discussions were conducted with 82 EN-INDEPTH survey interviewers and supervisors and 172 women between February and August 2018. Thematic analysis was guided by an a priori codebook.Results: Survey interview processes influenced reporting of pregnancy and APOs. Women found questions about APOs intrusive and of unclear relevance. Across all sites, sociocultural and spiritual beliefs were major barriers to women reporting pregnancy, due to fear that harm would come to their baby. We identified several factors affecting reporting of APOs including reluctance to speak about sad memories and variation in recognition of the baby's value, especially for APOs at earlier gestation. Overlaps in local understanding and terminology for APOs may also contribute to misreporting, for example between miscarriages and stillbirths. Interviewers' skills and training were the keys to enabling respondents to open up, as was privacy during interviews.Conclusion: Sociocultural beliefs and psycho-social impacts of APOs play a large part in underreporting these events. Interviewers' skills, careful tool development and translation are the keys to obtaining accurate information. Reporting could be improved with clearer explanations of survey purpose and benefits to respondents and enhanced interviewer training on probing, building rapport and empathy.
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| 21. |
- Newcombe, Virginia F J, et al.
(författare)
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Post-acute blood biomarkers and disease progression in traumatic brain injury.
- 2022
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Ingår i: Brain : a journal of neurology. - : Oxford University Press (OUP). - 1460-2156. ; 145:6, s. 2064-2076
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Tidskriftsartikel (refereegranskat)abstract
- There is substantial interest in the potential for traumatic brain injury to result in progressive neurological deterioration. While blood biomarkers such as glial fibrillary acid protein and neurofilament light have been widely explored in characterising acute traumatic brain injury, their use in the chronic phase is limited. Given increasing evidence that these proteins may be markers of ongoing neurodegeneration in a range of diseases, we examined their relationship to imaging changes and functional outcome in the months to years following traumatic brain injury. Two-hundred and three patients were recruited in two separate cohorts; six months post-injury (n=165); and >5 years post-injury (n=38; 12 of whom also provided data ∼8 months post-TBI). Subjects underwent blood biomarker sampling (n=199) and magnetic resonance imaging (n=172; including diffusion tensor imaging). Data from patient cohorts were compared to 59 healthy volunteers and 21 non-brain injury trauma controls. Mean diffusivity and fractional anisotropy were calculated in cortical grey matter, deep grey matter and whole brain white matter. Accelerated brain ageing was calculated at a whole brain level as the predicted age difference defined using T1-weighted images, and at a voxel-based level as the annualised Jacobian determinants in white matter and grey matter, referenced to a population of 652 healthy control subjects. Serum neurofilament light concentrations were elevated in the early chronic phase. While GFAP values were within the normal range at ∼8 months, many patients showed a secondary and temporally distinct elevations up to >5 years after injury. Biomarker elevation at six months was significantly related to metrics of microstructural injury on diffusion tensor imaging. Biomarker levels at ∼8 months predicted white matter volume loss at >5 years, and annualised brain volume loss between ∼8 months and 5 years. Patients who worsened functionally between ∼8 months and >5 years showed higher than predicted brain age and elevated neurofilament light levels. Glial fibrillary acid protein and neurofilament light levels can remain elevated months to years after traumatic brain injury, and show distinct temporal profiles. These elevations correlate closely with microstructural injury in both grey and white matter on contemporaneous quantitative diffusion tensor imaging. Neurofilament light elevations at ∼8 months may predict ongoing white matter and brain volume loss over >5 years of follow up. If confirmed, these findings suggest that blood biomarker levels at late time points could be used to identify traumatic brain injury survivors who are at high risk of progressive neurological damage.
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| 22. |
- Ruiz, Micaela B., et al.
(författare)
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Molecular responses of a key Antarctic species to sedimentation due to rapid climate change
- 2022
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Ingår i: Marine Environmental Research. - : Elsevier BV. - 0141-1136 .- 1879-0291. ; 180
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Tidskriftsartikel (refereegranskat)abstract
- Rapid regional warming causing glacial retreat and melting of ice caps in Antarctica leads benthic filter-feeders to be exposed to periods of food shortage and high respiratory impairment as a consequence of seasonal sediment discharge in the West Antarctic Peninsula coastal areas. The molecular physiological response and its fine-tuning allow species to survive acute environmental stress and are thus a prerequisite to longer-term adaptation to changing environments. Under experimental conditions, we analyzed here the metabolic response to changes in suspended sediment concentrations, through transcriptome sequencing and enzymatic measurements in a highly abundant Antarctic ascidian. We found that the mechanisms underlying short-term response to sedimentation in Cnemidocarpa verrucosa sp. A involved apoptosis, immune defense, and general metabolic depression. These mechanisms may be understood as an adaptive protection against sedimentation caused by glacial retreat. This process can strongly contribute to the structuring of future benthic filter-feeder communities in the face of climate change.
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| 23. |
- Tawil, Rabi, et al.
(författare)
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Safety and efficacy of losmapimod in facioscapulohumeral muscular dystrophy (ReDUX4): a randomised, double-blind, placebo-controlled phase 2b trial
- 2024
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Ingår i: Lancet Neurology. - : ELSEVIER SCIENCE INC. - 1474-4422 .- 1474-4465. ; 23:5, s. 477-486
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Tidskriftsartikel (refereegranskat)abstract
- Background Facioscapulohumeral muscular dystrophy is a hereditary progressive myopathy caused by aberrant expression of the transcription factor DUX4 in skeletal muscle. No approved disease-modifying treatments are available for this disorder. We aimed to assess the safety and efficacy of losmapimod (a small molecule that inhibits p38 alpha MAPK, a regulator of DUX4 expression, and p38 beta MAPK) for the treatment of facioscapulohumeral muscular dystrophy. Methods We did a randomised, double-blind, placebo-controlled phase 2b trial at 17 neurology centres in Canada, France, Spain, and the USA. We included adults aged 18-65 years with type 1 facioscapulohumeral muscular dystrophy (ie, with loss of repression of DUX4 expression, as ascertained by genotyping), a Ricci clinical severity score of 2-4, and at least one skeletal muscle judged using MRI to be suitable for biopsy. Participants were randomly allocated (1:1) to either oral losmapimod (15 mg twice a day) or matching placebo for 48 weeks, via an interactive response technology system. The investigator, study staff, participants, sponsor, primary outcome assessors, and study monitor were masked to the treatment allocation until study closure. The primary endpoint was change from baseline to either week 16 or 36 in DUX4driven gene expression in skeletal muscle biopsy samples, as measured by quantitative RT-PCR. The primary efficacy analysis was done in all participants who were randomly assigned and who had available data for assessment, according to the modified intention-to-treat principle. Safety and tolerability were assessed as secondary endpoints. This study is registered at ClinicalTrials.gov, number NCT04003974. The phase 2b trial is complete; an open-label extension is ongoing. Findings Between Aug 27, 2019, and Feb 27, 2020, 80 people were enrolled. 40 were randomly allocated to losmapimod and 40 to placebo. 54 (68%) participants were male and 26 (33%) were female, 70 (88%) were White, and mean age was 45<middle dot>7 (SD 12<middle dot>5) years. Least squares mean changes from baseline in DUX4driven gene expression did not differ significantly between the losmapimod (0<middle dot>83 [SE 0<middle dot>61]) and placebo (0<middle dot>40 [0<middle dot>65]) groups (difference 0<middle dot>43 [SE 0<middle dot>56; 95% CI -1<middle dot>04 to 1<middle dot>89]; p=0<middle dot>56). Losmapimod was well tolerated. 29 treatment-emergent adverse events (nine drugrelated) were reported in the losmapimod group compared with 23 (two drug-related) in the placebo group. Two participants in the losmapimod group had serious adverse events that were deemed unrelated to losmapimod by the investigators (alcohol poisoning and suicide attempt; postoperative wound infection) compared with none in the placebo group. No treatment discontinuations due to adverse events occurred and no participants died during the study. Interpretation Although losmapimod did not significantly change DUX4-driven gene expression, it was associated with potential improvements in prespecified structural outcomes (muscle fat infiltration), functional outcomes (reachable workspace, a measure of shoulder girdle function), and patient-reported global impression of change compared with placebo. These findings have informed the design and choice of efficacy endpoints for a phase 3 study of losmapimod in adults with facioscapulohumeral muscular dystrophy.
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| 24. |
- Thienel, Manuela, et al.
(författare)
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Immobility-associated thromboprotection is conserved across mammalian species from bear to human
- 2023
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 380:6641, s. 178-187
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Tidskriftsartikel (refereegranskat)abstract
- Venous thromboembolism (VTE) comprising deep venous thrombosis and pulmonary embolism is a major cause of morbidity and mortality. Short-term immobility-related conditions are a major risk factor for the development of VTE. Paradoxically, long-term immobilized free-ranging hibernating brown bears and paralyzed spinal cord injury (SCI) patients are protected from VTE. We aimed to identify mechanisms of immobility-associated VTE protection in a cross-species approach. Mass spectrometry-based proteomics revealed an antithrombotic signature in platelets of hibernating brown bears with heat shock protein 47 (HSP47) as the most substantially reduced protein. HSP47 down-regulation or ablation attenuated immune cell activation and neutrophil extracellular trap formation, contributing to thromboprotection in bears, SCI patients, and mice. This cross-species conserved platelet signature may give rise to antithrombotic therapeutics and prognostic markers beyond immobility-associated VTE.
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| 25. |
- Walsh, Roddy, et al.
(författare)
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Enhancing rare variant interpretation in inherited arrhythmias through quantitative analysis of consortium disease cohorts and population controls
- 2021
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Ingår i: Genetics in Medicine. - : Nature Publishing Group. - 1098-3600 .- 1530-0366. ; 23:1, s. 47-58
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Stringent variant interpretation guidelines can lead to high rates of variants of uncertain significance (VUS) for genetically heterogeneous disease like long QT syndrome (LQTS) and Brugada syndrome (BrS). Quantitative and disease-specific customization of American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) guidelines can address this false negative rate.Methods: We compared rare variant frequencies from 1847 LQTS (KCNQ1/KCNH2/SCN5A) and 3335 BrS (SCN5A) cases from the International LQTS/BrS Genetics Consortia to population-specific gnomAD data and developed disease-specific criteria for ACMG/AMP evidence classes-rarity (PM2/BS1 rules) and case enrichment of individual (PS4) and domain-specific (PM1) variants.Results: Rare SCN5A variant prevalence differed between European (20.8%) and Japanese (8.9%) BrS patients (p = 5.7 x 10(-18)) and diagnosis with spontaneous (28.7%) versus induced (15.8%) Brugada type 1 electrocardiogram (ECG) (p = 1.3 x 10(-13)). Ion channel transmembrane regions and specific N-terminus (KCNH2) and C-terminus (KCNQ1/KCNH2) domains were characterized by high enrichment of case variants and >95% probability of pathogenicity. Applying the customized rules, 17.4% of European BrS and 74.8% of European LQTS cases had (likely) pathogenic variants, compared with estimated diagnostic yields (case excess over gnomAD) of 19.2%/82.1%, reducing VUS prevalence to close to background rare variant frequency.Conclusion: Large case-control data sets enable quantitative implementation of ACMG/AMP guidelines and increased sensitivity for inherited arrhythmia genetic testing.
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| 26. |
- Widemann, Thomas, et al.
(författare)
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Venus Evolution Through Time : Key Science Questions, Selected Mission Concepts and Future Investigations
- 2023
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Ingår i: Space Science Reviews. - : SPRINGER. - 0038-6308 .- 1572-9672. ; 219:7
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Forskningsöversikt (refereegranskat)abstract
- In this work we discuss various selected mission concepts addressing Venus evolution through time. More specifically, we address investigations and payload instrument concepts supporting scientific goals and open questions presented in the companion articles of this volume. Also included are their related investigations (observations & modeling) and discussion of which measurements and future data products are needed to better constrain Venus' atmosphere, climate, surface, interior and habitability evolution through time. A new fleet of Venus missions has been selected, and new mission concepts will continue to be considered for future selections. Missions under development include radar-equipped ESA-led EnVision M5 orbiter mission (European Space Agency 2021), NASA-JPL's VERITAS orbiter mission (Smrekar et al. 2022a), NASA-GSFC's DAVINCI entry probe/flyby mission (Garvin et al. 2022a). The data acquired with the VERITAS, DAVINCI, and EnVision from the end of this decade will fundamentally improve our understanding of the planet's long term history, current activity and evolutionary path. We further describe future mission concepts and measurements beyond the current framework of selected missions, as well as the synergies between these mission concepts, ground-based and space-based observatories and facilities, laboratory measurements, and future algorithmic or modeling activities that pave the way for the development of a Venus program that extends into the 2040s (Wilson et al. 2022).
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