| 1. |
- Aad, G., et al.
(författare)
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- 2012
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swepub:Mat__t (refereegranskat)
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| 2. |
- Abazajian, Kevork, et al.
(författare)
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CMB-S4 : Forecasting Constraints on Primordial Gravitational Waves
- 2022
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 926:1
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Tidskriftsartikel (refereegranskat)abstract
- CMB-S4—the next-generation ground-based cosmic microwave background (CMB) experiment—is set to significantly advance the sensitivity of CMB measurements and enhance our understanding of the origin and evolution of the universe. Among the science cases pursued with CMB-S4, the quest for detecting primordial gravitational waves is a central driver of the experimental design. This work details the development of a forecasting framework that includes a power-spectrum-based semianalytic projection tool, targeted explicitly toward optimizing constraints on the tensor-to-scalar ratio, r, in the presence of Galactic foregrounds and gravitational lensing of the CMB. This framework is unique in its direct use of information from the achieved performance of current Stage 2–3 CMB experiments to robustly forecast the science reach of upcoming CMB-polarization endeavors. The methodology allows for rapid iteration over experimental configurations and offers a flexible way to optimize the design of future experiments, given a desired scientific goal. To form a closed-loop process, we couple this semianalytic tool with map-based validation studies, which allow for the injection of additional complexity and verification of our forecasts with several independent analysis methods. We document multiple rounds of forecasts for CMB-S4 using this process and the resulting establishment of the current reference design of the primordial gravitational-wave component of the Stage-4 experiment, optimized to achieve our science goals of detecting primordial gravitational waves for r > 0.003 at greater than 5σ, or in the absence of a detection, of reaching an upper limit of r < 0.001 at 95% CL.
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| 3. |
- Michaut, Magali, et al.
(författare)
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Integration of genomic, transcriptomic and proteomic data identifies two biologically distinct subtypes of invasive lobular breast cancer.
- 2016
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- Invasive lobular carcinoma (ILC) is the second most frequently occurring histological breast cancer subtype after invasive ductal carcinoma (IDC), accounting for around 10% of all breast cancers. The molecular processes that drive the development of ILC are still largely unknown. We have performed a comprehensive genomic, transcriptomic and proteomic analysis of a large ILC patient cohort and present here an integrated molecular portrait of ILC. Mutations in CDH1 and in the PI3K pathway are the most frequent molecular alterations in ILC. We identified two main subtypes of ILCs: (i) an immune related subtype with mRNA up-regulation of PD-L1, PD-1 and CTLA-4 and greater sensitivity to DNA-damaging agents in representative cell line models; (ii) a hormone related subtype, associated with Epithelial to Mesenchymal Transition (EMT), and gain of chromosomes 1q and 8q and loss of chromosome 11q. Using the somatic mutation rate and eIF4B protein level, we identified three groups with different clinical outcomes, including a group with extremely good prognosis. We provide a comprehensive overview of the molecular alterations driving ILC and have explored links with therapy response. This molecular characterization may help to tailor treatment of ILC through the application of specific targeted, chemo- and/or immune-therapies.
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| 4. |
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| 5. |
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| 6. |
- Bard-Chapeau, Emilie A, et al.
(författare)
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Transposon mutagenesis identifies genes driving hepatocellular carcinoma in a chronic hepatitis B mouse model.
- 2014
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 46:1
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Tidskriftsartikel (refereegranskat)abstract
- The most common risk factor for developing hepatocellular carcinoma (HCC) is chronic infection with hepatitis B virus (HBV). To better understand the evolutionary forces driving HCC, we performed a near-saturating transposon mutagenesis screen in a mouse HBV model of HCC. This screen identified 21 candidate early stage drivers and a very large number (2,860) of candidate later stage drivers that were enriched for genes that are mutated, deregulated or functioning in signaling pathways important for human HCC, with a striking 1,199 genes being linked to cellular metabolic processes. Our study provides a comprehensive overview of the genetic landscape of HCC.
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| 7. |
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| 8. |
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| 9. |
- Jungclaus, Johann H., et al.
(författare)
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The PMIP4 contribution to CMIP6 - Part 3 : The last millennium, scientific objective, and experimental design for the PMIP4 past1000 simulations
- 2017
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Ingår i: Geoscientific Model Development. - : Copernicus GmbH. - 1991-959X .- 1991-9603. ; 10:11, s. 4005-4033
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Tidskriftsartikel (refereegranskat)abstract
- The pre-industrial millennium is among the periods selected by the Paleoclimate Model Intercomparison Project (PMIP) for experiments contributing to the sixth phase of the Coupled Model Intercomparison Project (CMIP6) and the fourth phase of the PMIP (PMIP4). The past1000 transient simulations serve to investigate the response to (mainly) natural forcing under background conditions not too different from today, and to discriminate between forced and internally generated variability on interannual to centennial timescales. This paper describes the motivation and the experimental set-ups for the PMIP4-CMIP6 past1000 simulations, and discusses the forcing agents orbital, solar, volcanic, and land use/land cover changes, and variations in greenhouse gas concentrations. The past1000 simulations covering the pre-industrial millennium from 850 Common Era (CE) to 1849 CE have to be complemented by historical simulations (1850 to 2014 CE) following the CMIP6 protocol. The external forcings for the past1000 experiments have been adapted to provide a seamless transition across these time periods. Protocols for the past1000 simulations have been divided into three tiers. A default forcing data set has been defined for the Tier 1 (the CMIP6 past1000) experiment. However, the PMIP community has maintained the flexibility to conduct coordinated sensitivity experiments to explore uncertainty in forcing reconstructions as well as parameter uncertainty in dedicated Tier 2 simulations. Additional experiments (Tier 3) are defined to foster collaborative model experiments focusing on the early instrumental period and to extend the temporal range and the scope of the simulations. This paper outlines current and future research foci and common analyses for collaborative work between the PMIP and the observational communities (reconstructions, instrumental data).
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| 10. |
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| 11. |
- Schmidt, G. A., et al.
(författare)
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Climate forcing reconstructions for use in PMIP simulations of the last millennium (v1.0)
- 2011
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Ingår i: Geoscientific Model Development. - : Copernicus GmbH. - 1991-959X .- 1991-9603. ; 4:1, s. 33-45
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Tidskriftsartikel (refereegranskat)abstract
- Simulations of climate over the Last Millennium (850-1850 CE) have been incorporated into the third phase of the Paleoclimate Modelling Intercomparison Project (PMIP3). The drivers of climate over this period are chiefly orbital, solar, volcanic, changes in land use/land cover and some variation in greenhouse gas levels. While some of these effects can be easily defined, the reconstructions of solar, volcanic and land use-related forcing are more uncertain. We describe here the approach taken in defining the scenarios used in PMIP3, document the forcing reconstructions and discuss likely implications.
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| 12. |
- Schmidt, G. A., et al.
(författare)
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Climate forcing reconstructions for use in PMIP simulations of the last millennium (v1.0)
- 2010
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Ingår i: Geoscientific Model Development. - : Copernicus GmbH. - 1991-959X. ; 3:3, s. 1549-1586
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Tidskriftsartikel (refereegranskat)abstract
- Simulations of climate over the Last Millennium (850-1850 CE) have been incorporated into the third phase of the Paleoclimate Modelling Intercomparison Project (PMIP3). The drivers of climate over this period are chiefly orbital, solar, volcanic, changes in land use/land cover and some variation in greenhouse gas levels. While some of these effects can be easily defined, the reconstructions of solar, volcanic and land use-related forcing are more uncertain. We describe here the approach taken in defining the scenarios used in PMIP3, document the forcing reconstructions and discuss likely implications.
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| 13. |
- Schmidt, G. A., et al.
(författare)
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Climate forcing reconstructions for use in PMIP simulations of the Last Millennium (v1.1)
- 2012
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Ingår i: Geoscientific Model Development. - : Copernicus GmbH. - 1991-959X .- 1991-9603. ; 5:1, s. 185-191
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Tidskriftsartikel (refereegranskat)abstract
- We update the forcings for the PMIP3 experiments for the Last Millennium to include new assessments of historical land use changes and discuss new suggestions for calibrating solar activity proxies to total solar irradiance.
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| 14. |
- Haraldsen, Heidi M. M., et al.
(författare)
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An exploration of reciprocity among teacher and students in female pre-professional ballet education : a shared reality theory perspective
- 2023
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Ingår i: Frontiers in Education. - : Frontiers Media S.A.. - 2504-284X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of the present study was to explore perceptions of shared reality in teacher-student partnerships in ballet, and how these perceptions were related to experiences of quality in the relationship and well-being. A longitudinal qualitative study design was adopted, with three female ballet students and their teacher participating in three semi-structured interviews each over an eight-month period. Data were analyzed using a combination of thematic and narrative analysis. Findings indicated that across the teacher-student relationships there were perceptions of a shared reality only on the professional and distanced level and not on a relational and personal level. This was achieved by a common experience of what matters in the world of ballet education as well as students finding their teacher as trustworthy. Furthermore, it appeared that the authoritarian apprenticeship culture in ballet, where the teachers give clear instructions and feedback, and where the student role is to listen and adapt to the teacher's instructions, was a barrier to fully achieving a shared reality on a personal and deeper level. In turn, this influenced the quality of the relationship and the wellbeing of both teacher and students. The present study offers critical reflections on the cultural backdrop of teaching and learning in ballet and highlights the importance of teachers to facilitate a supportive, unconditional, and trustworthy relationship so that they can work together in a more productive manner.
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| 15. |
- Heaton, T. J., et al.
(författare)
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Radiocarbon : A key tracer for studying Earth’s dynamo, climate system, carbon cycle, and Sun
- 2021
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 374:6568
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Forskningsöversikt (refereegranskat)abstract
- Radiocarbon (14C), as a consequence of its production in the atmosphere and subsequent dispersal through the carbon cycle, is a key tracer for studying the Earth system. Knowledge of past 14C levels improves our understanding of climate processes, the Sun, the geodynamo, and the carbon cycle. Recently updated radiocarbon calibration curves (IntCal20, SHCal20, and Marine20) provide unprecedented accuracy in our estimates of 14C levels back to the limit of the 14C technique (~55,000 years ago). Such improved detail creates new opportunities to probe the Earth and climate system more reliably and at finer scale. We summarize the advances that have underpinned this revised set of radiocarbon calibration curves, survey the broad scientific landscape where additional detail on past 14C provides insight, and identify open challenges for the future.
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| 16. |
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| 17. |
- Lorand, Jean-Pierre, et al.
(författare)
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The sulfur budget and sulfur isotopic composition of Martian regolith breccia NWA 7533
- 2020
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Ingår i: Meteoritics and Planetary Science. - : John Wiley & Sons, Ltd. - 1086-9379 .- 1945-5100. ; 55:9, s. 2097-2116
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Tidskriftsartikel (refereegranskat)abstract
- The sulfur isotope budget of Martian regolith breccia (NWA 7533) has been addressed from conventional fluorination bulk rock analyses and ion microprobe in situ analyses. The bulk rock analyses yield 865 ± 50 ppm S in agreement with LA-ICP-MS analyses. These new data support previous estimates of 80% S loss resulting from terrestrial weathering of NWA 7533 pyrite. Pyrite is by far the major S host. Apatite and Fe oxyhydroxides are negligible S carriers, as are the few tiny igneous pyrrhotite-pentlandite sulfide grains included in lithic clasts so far identified. A small nonzero delta-33S (-0.029 ± 0.010) signal is clearly resolved at the 2σ level in the bulk rock analyses, coupled with negative CDT-normalized δ34S (-2.54 ± 0.10 permil) and near-zero delta-36S (0.002 ± 0.09 permil). In situ analyses also yield negative delta-33S values (-0.05 to -0.30 permil) with only a few positive delta-33S up to +0.38 permil. The slight discrepancy compared to the bulk rock results is attributed to a possible sampling bias. The occurrence of mass-independent fractionation (MIF) supports a model of NWA 7533 pyrite formation from surface sulfur that experienced photochemical reaction(s). The driving force that recycled crustal S in NWA 7533 lithologies - magmatic intrusions or impact-induced heat - is presently unclear. However, in situ analyses also gave negative δ34S values (+1 to -5.8 permil). Such negative values in the hydrothermal setting of NWA 7533 are reflective of hydrothermal sulfides precipitated from H2S/HS- aqueous fluid produced via open-system thermochemical reduction of sulfates at high temperatures (>300 °C).
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| 18. |
- Reimer, Paula J., et al.
(författare)
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The IntCal20 Northern Hemisphere Radiocarbon Age Calibration Curve (0-55 cal kBP)
- 2020
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Ingår i: Radiocarbon. - 0033-8222. ; 62:4, s. 725-757
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Tidskriftsartikel (refereegranskat)abstract
- Radiocarbon (C) ages cannot provide absolutely dated chronologies for archaeological or paleoenvironmental studies directly but must be converted to calendar age equivalents using a calibration curve compensating for fluctuations in atmospheric C concentration. Although calibration curves are constructed from independently dated archives, they invariably require revision as new data become available and our understanding of the Earth system improves. In this volume the international C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP. Based on tree rings, IntCal20 now extends as a fully atmospheric record to ca. 13,900 cal BP. For the older part of the timescale, IntCal20 comprises statistically integrated evidence from floating tree-ring chronologies, lacustrine and marine sediments, speleothems, and corals. We utilized improved evaluation of the timescales and location variable C offsets from the atmosphere (reservoir age, dead carbon fraction) for each dataset. New statistical methods have refined the structure of the calibration curves while maintaining a robust treatment of uncertainties in the C ages, the calendar ages and other corrections. The inclusion of modeled marine reservoir ages derived from a three-dimensional ocean circulation model has allowed us to apply more appropriate reservoir corrections to the marine C data rather than the previous use of constant regional offsets from the atmosphere. Here we provide an overview of the new and revised datasets and the associated methods used for the construction of the IntCal20 curve and explore potential regional offsets for tree-ring data. We discuss the main differences with respect to the previous calibration curve, IntCal13, and some of the implications for archaeology and geosciences ranging from the recent past to the time of the extinction of the Neanderthals.
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| 19. |
- Sayadi, Ahmed, et al.
(författare)
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Functional features of EVI1 and EVI1Δ324 isoforms of MECOM gene in genome-wide transcription regulation and oncogenicity.
- 2016
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Ingår i: Oncogene. - : Macmillan Publishers Ltd.. - 0950-9232 .- 1476-5594. ; 35:18, s. 2311-2321
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Tidskriftsartikel (refereegranskat)abstract
- The MDS1 and ecotropic viral integration site 1 (EVI1) complex locus (MECOM) gene encodes several transcription factor variants including MDS1-EVI1, EVI1 and EVI1Δ324. Although MDS1-EVI1 has been associated with tumor-suppressing activity, EVI1 is a known oncogene in various cancers, whose expression is associated with poor patient survival. Although EVI1Δ324 is co-transcribed with EVI1, its activity in cancer cells is not fully understood. Previous reports described that unlike EVI1, EVI1Δ324 protein cannot transform fibroblasts because of its disrupted N-terminal zinc finger (ZNF) domain. To better understand EVI1Δ324 biology and function, we obtained genome-wide binding occupancies and expression data in ovarian cancer cells. We characterized its DNA-binding sites, binding motif and target genes. Comparative analyses with previous study show that EVI1 and EVI1Δ324 share similar transcriptional activities linked to their common C-terminus ZNF domain. They bind to an E-twenty-six family (ETS)-like motif, target to a large extent the same genes and cooperate with AP1 transcription factor. EVI1Δ324-occupied genes were 70.7% similar to EVI1-bound genes. More strikingly, EVI1 and EVI1Δ324 differentially expressed genes were 99.87% identical, indicating comparable transcriptional regulatory functions. Consistently with gene ontologies linked to these target genes, EVI1Δ324 expression in HeLa cells could enhance anchorage-independent growth, such as EVI1, showing that EVI1Δ324 expression also lead to pro-oncogenic effects. The main specific feature of EVI1 variant is its N-terminus ZNF domain that binds DNA through GATA-like motif. We found that most GATA-like EVI1 chromatin immunoprecipitation sequencing peaks are far from genes and are not involved in transcriptional regulation. These genomic regions were enriched in simple sequence repeats and displayed high meiotic recombination rates. Overall, our genomics analyses uncovered common and specific features of two major MECOM isoforms. Their influence on transcription and downstream cell proliferation was comparable. However, EVI1-specific GATA-like binding sites, from its N-terminus ZNF domain, associated with high recombination rates, suggesting possible additional oncogenic potential for EVI1 in modulating genomic stability.
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| 20. |
- Schofield, PN, et al.
(författare)
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Pathbase: a database of mutant mouse pathology
- 2004
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Ingår i: Nucleic acids research. - : Oxford University Press (OUP). - 1362-4962. ; 32:Database issue, s. D512-D515
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Tidskriftsartikel (refereegranskat)
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| 21. |
- Schouten, Stefan, et al.
(författare)
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An interlaboratory study of TEX86 and BIT analysis of sediments, extracts, and standard mixtures
- 2013
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Ingår i: Geochemistry Geophysics Geosystems. - 1525-2027. ; 14:12, s. 5263-5285
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Tidskriftsartikel (refereegranskat)abstract
- Two commonly used proxies based on the distribution of glycerol dialkyl glycerol tetraethers (GDGTs) are the TEX86 (TetraEther indeX of 86 carbon atoms) paleothermometer for sea surface temperature reconstructions and the BIT (Branched Isoprenoid Tetraether) index for reconstructing soil organic matter input to the ocean. An initial round-robin study of two sediment extracts, in which 15 laboratories participated, showed relatively consistent TEX86 values (reproducibility +/- 3-4 degrees C when translated to temperature) but a large spread in BIT measurements (reproducibility +/- 0.41 on a scale of 0-1). Here we report results of a second round-robin study with 35 laboratories in which three sediments, one sediment extract, and two mixtures of pure, isolated GDGTs were analyzed. The results for TEX86 and BIT index showed improvement compared to the previous round-robin study. The reproducibility, indicating interlaboratory variation, of TEX86 values ranged from 1.3 to 3.0 degrees C when translated to temperature. These results are similar to those of other temperature proxies used in paleoceanography. Comparison of the results obtained from one of the three sediments showed that TEX86 and BIT indices are not significantly affected by interlaboratory differences in sediment extraction techniques. BIT values of the sediments and extracts were at the extremes of the index with values close to 0 or 1, and showed good reproducibility (ranging from 0.013 to 0.042). However, the measured BIT values for the two GDGT mixtures, with known molar ratios of crenarchaeol and branched GDGTs, had intermediate BIT values and showed poor reproducibility and a large overestimation of the true (i.e., molar-based) BIT index. The latter is likely due to, among other factors, the higher mass spectrometric response of branched GDGTs compared to crenarchaeol, which also varies among mass spectrometers. Correction for this different mass spectrometric response showed a considerable improvement in the reproducibility of BIT index measurements among laboratories, as well as a substantially improved estimation of molar-based BIT values. This suggests that standard mixtures should be used in order to obtain consistent, and molar-based, BIT values.
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| 22. |
- Alme, Tomas Nordheim, et al.
(författare)
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Chronic fatigue syndromes: real illnesses that people can recover from
- 2023
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Ingår i: Scandinavian Journal of Primary Health Care. - : TAYLOR & FRANCIS LTD. - 0281-3432 .- 1502-7724. ; 41:4, s. 372-376
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Tidskriftsartikel (refereegranskat)abstract
- The Oslo Chronic Fatigue Consortium consists of researchers and clinicians who question the current narrative that chronic fatigue syndromes, including post-covid conditions, are incurable diseases. Instead, we propose an alternative view, based on research, which offers more hope to patients. Whilst we regard the symptoms of these conditions as real, we propose that they are more likely to reflect the brains response to a range of biological, psychological, and social factors, rather than a specific disease process. Possible causes include persistent activation of the neurobiological stress response, accompanied by associated changes in immunological, hormonal, cognitive and behavioural domains. We further propose that the symptoms are more likely to persist if they are perceived as threatening, and all activities that are perceived to worsen them are avoided. We also question the idea that the best way to cope with the illness is by prolonged rest, social isolation, and sensory deprivation.Instead, we propose that recovery is often possible if patients are helped to adopt a less threatening understanding of their symptoms and are supported in a gradual return to normal activities. Finally, we call for a much more open and constructive dialogue about these conditions. This dialogue should include a wider range of views, including those of patients who have recovered from them.
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| 23. |
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| 24. |
- Arvidsson, Emma, et al.
(författare)
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Quantification of the absorption and scattering effects of diffusers in a room with absorbent ceiling
- 2021
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Ingår i: Buildings. - : MDPI AG. - 2075-5309. ; 11:12
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Tidskriftsartikel (refereegranskat)abstract
- In ordinary public rooms, such as classrooms and offices, an absorbent ceiling is the typical first acoustic action. This treatment provides a good acoustic baseline. However, an improvement of specific room acoustic parameters, operating for specific frequencies, can be needed. It has been seen that diffusing elements can be effective additional treatment. In order to choose the right design, placement, and quantity of diffusers, a model to estimate the effect on the acoustics is necessary. This study evaluated whether an SEA model could be used for that purpose, particularly for the cases where diffusers are used in combination with an absorbent ceiling. It was investigated whether the model could handle different quantities of diffusing elements, varied diffusion characteristics, and varied installation patterns. It was found that the model was sensitive to these changes, given that the output from the model in terms of acoustic properties will be reflected by the change of diffuser configuration design. It was also seen that the absorption and scattering of the diffusers could be quantified in a laboratory environment: a reverberation chamber. Through the SEA model, these quantities could be transformed to a full-scale room for estimation of the room acoustic parameters.
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| 25. |
- Arvidsson, Emma, et al.
(författare)
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Subjective experience of speech depending on the acoustic treatment in an ordinary room
- 2021
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Ingår i: International Journal of Environmental Research and Public Health. - : MDPI AG. - 1661-7827 .- 1660-4601. ; 18:23
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Tidskriftsartikel (refereegranskat)abstract
- In environments such as classrooms and offices, complex tasks are performed. A satisfac-tory acoustic environment is critical for the performance of such tasks. To ensure a good acoustic environment, the right acoustic treatment must be used. The relation between different room acoustic treatments and how they affect speech perception in these types of rooms is not yet fully under-stood. In this study, speech perception was evaluated for three different configurations using ab-sorbers and diffusers. Twenty-nine participants reported on their subjective experience of speech in respect of different configurations in different positions in a room. They judged sound quality and attributes related to speech perception. In addition, the jury members ranked the different acoustic environments. The subjective experience was related to the different room acoustic treatments and the room acoustic parameters of speech clarity, reverberation time and sound strength. It was found that people, on average, rated treatments with a high degree of absorption as best. This configura-tion had the highest speech clarity value and lowest values for reverberation time and sound strength. The perceived sound quality could be correlated to speech clarity, while attributes related to speech perception had the strongest association with reverberation time.
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| 26. |
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| 27. |
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| 28. |
- Bard, D., et al.
(författare)
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A finite element solution of structure-borne sound attenuation for a lightweight timber floor
- 2008
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Ingår i: Building Acoustics. - : SAGE Publications. - 1351-010X .- 2059-8025. ; 15:2, s. 137-152
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Tidskriftsartikel (refereegranskat)abstract
- Structure-borne sound attenuation of lightweight timber floor structures has been investigated by high-resolution numerical calculation methods. Two models have been studied both experimentally and numerically. The first considers a continuous chipboard plate and a supporting beam. The second considers two plates that are fastened on one beam. Damping effects, which arise from the two different discontinuities, are included. The real-valued modulus of elasticity is replaced with a complex value. In the calculations, the orthotropic material characteristics of the building material have also been taken into account. The results from the calculations and laboratory measurement confirm that the attenuation rate is highly dependent on the excitation location, if all the other parameters remain the same.
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| 29. |
- Bard, Delphine, et al.
(författare)
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Reflection and transmission properties of wooden wall/floor building elements
- 2011
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Ingår i: 18th International Congress on Sound and Vibration 2011, ICSV 2011. - 9781618392596 ; 2, s. 1065-1072
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Konferensbidrag (refereegranskat)abstract
- Various modal methods are frequently used to investigate the vibration pattern in construction elements of a building in the low frequency range. The experimental determination of time average transmission and reflection coefficient has been developed for the large scale building structures. In this study, we investigate a mock up of a wall/floor junction. The wave approach is combined with the continuity equation. In this fashion both the flexural wave propagation and the in-plane wave motion can be captured. The miss-match impedance was also an important factor, since there is a change of material in the junction. The goal of using scattering matrix formulation is to separate the transmitted wave and the reflected wave as the structural wave propagates towards a wall/floor junction, but also to calculate the rate of wave conversion. One type of junction has been studied with the help of accelerometer matrices: the T junction of the floor/wall structure with its reinforcement beams.
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| 30. |
- Bard, D., et al.
(författare)
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Vibrations analysis in high-tech facility : A swedish light synchrotron
- 2010
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Ingår i: 17th International Congress on Sound and Vibration 2010 : ICSV 17 - ICSV 17. - 9781617822551 ; 4, s. 2811-2818
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Konferensbidrag (refereegranskat)abstract
- MAX-lab is a national laboratory operated jointly by the Swedish Research Council and Lund University. As of today, the MAX project consists of three facilities, (three storage rings): MAX-I, MAX-II, MAX-III and one electron pre-accelerator called MAX-Injector. A new storage ring is needed at the benefit of material science, such as nanotechnology. MAX-IV will be 100 times more efficient than existing synchrotron radiation facilities. MAX-IV will consist of a main source that will be a 3-GeV ring with state-of-the-art low emittance for the production of soft and hard x-rays as well as an expansion into the free electron laser field. The second source, the Linac injector, will provide short pulses to a short pulse facility. It will be built as an underground tunnel next to the main ring. The main objective of the present work is to study vibrations at the foundation of the light synchrotron subjected to different excitations and analyze the influence of the surrounding vibration sources on the MAX-IV Lab's underground tunnel. Since MAX-IV will be used for high precision measurements, it will be asked to have very strict technical conditions where only very low vibration levels will be allowed. The aim is to establish realistic finite element models that predict vibrations in the foundation and in the Linac with high accuracy. To achieve this purpose it will be necessary to model loads, materials, etc. with different assumptions, in order to prove the fulfillment of the needed requirements. The vibrations are analyzed by the finite element method in both transient and steady state solutions. The ring model contains the concrete floor structure, the concrete structure of the beam containment and the soil up to a depth of about 10m and extending to the nearby roads, while Linac's model has the tunnel itself, the soil (up to 10 m deep also) and the crossing bridge over it.
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| 31. |
- Benomar, Anass, et al.
(författare)
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Nonaneurysmal perimesencephalic subarachnoid hemorrhage on noncontrast head CT: An accuracy, inter-rater, and intra-rater reliability study
- 2024
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Ingår i: Journal of neuroradiology. - : MASSON EDITEUR. - 0150-9861 .- 1773-0406. ; 51:4
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Tidskriftsartikel (refereegranskat)abstract
- Background and purpose: To evaluate the reliability and accuracy of nonaneurysmal perimesencephalic subarachnoid hemorrhage (NAPSAH) on Noncontrast Head CT (NCCT) between numerous raters. Materials and methods: 45 NCCT of adult patients with SAH who also had a catheter angiography (CA) were independently evaluated by 48 diverse raters; 45 raters performed a second assessment one month later. For each case, raters were asked: 1) whether they judged the bleeding pattern to be perimesencephalic; 2) whether there was blood anterior to brainstem; 3) complete filling of the anterior interhemispheric fissure (AIF); 4) extension to the lateral part of the sylvian fissure (LSF); 5) frank intraventricular hemorrhage; 6) whether in the hypothetical presence of a negative CT angiogram they would still recommend CA. An automatic NAPSAH diagnosis was also generated by combining responses to questions 2 -5. Reliability was estimated using Gwet 's AC1 ( K G ), and the relationship between the NCCT diagnosis of NAPSAH and the recommendation to perform CA using Cramer 's V test. Multi -rater accuracy of NCCT in predicting negative CA was explored. Results: Inter -rater reliability for the presence of NAPSAH was moderate ( K G = 0.58; 95%CI: 0.47, 0.69), but improved to substantial when automatically generated ( K G = 0.70; 95%CI: 0.59, 0.81). The most reliable criteria were the absence of AIF filling ( K G = 0.79) and extension to LSF ( K G = 0.79). Mean intra-rater reliability was substantial ( K G = 0.65). NAPSAH weakly correlated with CA decision ( V = 0.50). Mean sensitivity and specificity were 58% (95%CI: 44%, 71%) and 83 % (95%CI: 72 %, 94%), respectively. Conclusion: NAPSAH remains a diagnosis of exclusion. The NCCT diagnosis was moderately reliable and its impact on clinical decisions modest. (c) 2024 The Authors. Published by Elsevier Masson SAS. This is an open access article under the CC BY -NC -ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
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| 32. |
- Costa, Nathalia, et al.
(författare)
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A Definition of "Flare" in Low Back Pain: A Multiphase Process Involving Perspectives of Individuals With Low Back Pain and Expert Consensus
- 2019
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Ingår i: Journal of Pain. - : CHURCHILL LIVINGSTONE. - 1526-5900 .- 1528-8447. ; 20:11, s. 1267-1275
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Tidskriftsartikel (refereegranskat)abstract
- Low back pain (LBP) varies over time. Consumers, clinicians, and researchers use various terms to describe LBP fluctuations, such as episodes, recurrences and flares. Although "flare" is use commonly, there is no consensus on how it is defined. This study aimed to obtain consensus for a LBP flare definition using a mixed-method approach. Step 1 involved the derivation of a preliminary candidate flare definition based on thematic analysis of views of 130 consumers in consultation with an expert consumer writer. In step 2, a workshop was conducted to incorporate perspectives of 19 LBP experts into the preliminary flare definition, which resulted in 2 alternative LBP flare definitions. Step 3 refined the definition using a 2-round Delphi consensus with 50 experts in musculoskeletal conditions. The definition favored by experts was further tested with 16 individuals with LBP in step 4, using the definition in three scenarios. This multiphase study produced a definition of LBP flare that distinguishes it from other LBP fluctuations, represents consumers views, involves expert consensus, and is understandable by consumers in clinical and research contexts: "A flare-up is a worsening of your condition that lasts from hours to weeks that is difficult to tolerate and generally impacts your usual activities and/or emotions." Perspective: A multiphase process, incorporating consumers views and expert consensus, produced a definition of LBP flare that distinguishes it from other LBP fluctuations. (C) 2019 by the American Pain Society
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| 33. |
- El Albani, Abderrazak, et al.
(författare)
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The 2.1 Ga old Francevillian biota: biogenicity, taphonomy and biodiversity.
- 2014
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:6:e99438, s. 1-18
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Tidskriftsartikel (refereegranskat)abstract
- The Paleoproterozoic Era witnessed crucial steps in the evolution of Earth’s surface environments following the first appreciable rise of free atmospheric oxygen concentrations ~2.3 to 2.1 Ga ago, and concomitant shallow ocean oxygenation. While most sedimentary successions deposited during this time interval have experienced thermal overprinting from burial diagenesis and metamorphism, the ca. 2.1 Ga black shales of the Francevillian B Formation (FB2) cropping out in southeastern Gabon have not. The Francevillian Formation contains centimeter-sized structures interpreted as organized and spatially discrete populations of colonial organisms living in an oxygenated marine ecosystem. Here, new material from the FB2 black shales is presented and analyzed to further explore its biogenicity and taphonomy. Our extended record comprises variably sized, shaped, and structured pyritized macrofossils of lobate, elongated, and rodshaped morphologies as well as abundant non-pyritized disk-shaped macrofossils and organic-walled acritarchs. Combined microtomography, geochemistry, and sedimentary analysis suggest a biota fossilized during early diagenesis. The emergence of this biota follows a rise in atmospheric oxygen, which is consistent with the idea that surface oxygenation allowed the evolution and ecological expansion of complex megascopic life.
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| 34. |
- Karatzas, Xanthias, et al.
(författare)
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Characterization and optimization of an autothermal diesel and jet fuel reformer for 5 kW(e) mobile fuel cell applications
- 2010
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Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947 .- 1873-3212. ; 156:2, s. 366-379
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Tidskriftsartikel (refereegranskat)abstract
- The present paper describes the characterization of an autothermal reformer designed to generate hydrogen by autothermal reforming (ATR) from commercial diesel fuel (similar to 10 ppm S) and jet fuel (similar to 200 ppm S) for a 5 kW(e) polymer electrolyte fuel cell (PEFC). Commercial noble metal-based catalysts supported on 900 cpsi cordierite monoliths substrates were used for ATR with reproducible results. Parameters investigated in this study were the variation of the fuel inlet temperature, fuel flow and the H2O/C and O-2/C ratios. Temperature profiles were studied both in the axial and radial directions of the reformer. Product gas composition was analyzed using gas chromatography. It was concluded from the experiments that an elevated fuel inlet temperature (>= 60 degrees C) and a higher degree of fuel dispersion, generated via a single-fluid pressurized-swirl nozzle at high fuel flow, significantly improved the performance of the reformer. Complete fuel conversion, a reforming efficiency of 81% and an H-2 selectivity of 96% were established for ATR of diesel at P=5kW(e), H2O/C = 2.5, O-2/C = 0.49 and a fuel inlet temperature of 60 degrees C. No hot-spot formation and negligible coke formation were observed in the reactor at these operating conditions. The reforming of jet fuel resulted in a reforming efficiency of only 42%. A plausible cause is the coke deposition, originating from the aromatics present in the fuel, and the adsorption of S-compounds on the active sites of the reforming catalyst. Our results indicate possibilities for the developed catalytic reformer to be used in mobile fuel cell applications for energy-efficient hydrogen production from diesel fuel.
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| 35. |
- Negreira, J., et al.
(författare)
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Low frequency vibroacoustic investigation of wooden T-junctions
- 2016
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Ingår i: Applied Acoustics. - : Elsevier BV. - 0003-682X. ; 105, s. 1-12
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, an experimental investigation on the influence of glue on the low frequency vibroacoustic performance (up to 200 Hz) of wooden T-junctions is presented along with a discussion of modelling issues related to the junctions. The mock-ups studied represent cut-outs of full size timber floor assemblies typically used in Sweden. Their dynamic performance was first studied experimentally by means of modal analysis. Moreover, finite element (FE) simulations of the T-junctions were carried out to establish reliable prediction tools, using the measurement data as calibration input. Modelling issues were addressed to investigate the influence of different features that must be taken into account when simulating the connections as part of larger structures. Guidelines for modelling these type of connections, when developing low frequency FE predictive tools, are presented here.
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| 36. |
- Nilsson, Marita, et al.
(författare)
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Hydrogen generation from dimethyl ether for fuel cell auxiliary power units
- 2006
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Ingår i: Energy & Fuels. - : American Chemical Society (ACS). - 0887-0624 .- 1520-5029. ; 20:5, s. 2164-2169
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Tidskriftsartikel (refereegranskat)abstract
- Copper-based catalysts have been evaluated for the combined partial oxidation and steam reforming of dimethyl ether (DME) in a reformer designed to produce hydrogen for a full-scale heavy-duty truck auxiliary power unit. The experiments were conducted using gas mixtures similar to realistic operating conditions. A Pd-promoted CuZn catalyst was found to be highly selective for hydrogen production from DME at O-2/DME = 0.25 and H2O/ DME = 2.5. The catalysts were characterized using Brunauer-Emmett-Teller surface area measurement, X-ray diffraction, and temperature-programmed reduction. The copper surface area was determined by pulse chemisorption of nitrous oxide. In addition to the reforming catalyst evaluation, a startup sequence was tested, where DME was catalytically ignited and combusted over platinum or iron oxide catalysts.
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| 37. |
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| 38. |
- Sjöström, Anders, et al.
(författare)
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Modeling walking on a lightweight wooden floor
- 2015
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Ingår i: 44th International Congress and Exposition on Noise Control Engineering (Internoise 2015) : Implementing Noise Control Technology - Implementing Noise Control Technology. - 9781510810822 ; , s. 6263-6270
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Konferensbidrag (refereegranskat)abstract
- The most common sound insulation problem for lightweight timber structures is impact sounds from people walking. This is especially apparent in the low frequency range, due to differences in weight, stiffness, density and repartitioning as compared to more traditional materials. As lightweight timber structures increase their market share, the understanding of their behaviour and the ability to predict the production and spread of these impact sounds by numerical models during the design phase of a building, become more important. The subject of this paper is a typical wooden floor constructed from particleboards on top of wooden beams. The floor is subjected to loads from test subjects walking on the floor. We compare measurements on this floor with simulations of the same floor construct using a finite element model with idealised walking loads. The frequency range of interest here is from 20Hz to 200Hz. The aim of the comparison is to create an accurate model of the floor that can capture the behaviour of the real structure and that can be used in subsequent models of larger structures i.e. multi-storey wooden buildings.
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| 39. |
- Solstad, Bard Erlend, et al.
(författare)
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An exploration of reciprocity between female athletes and their coach in elite junior swimming : a shared reality theory perspective
- 2022
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Ingår i: Qualitative Research in Sport, Exercise and Health. - : Taylor & Francis. - 2159-676X .- 2159-6778. ; 14:4, s. 545-563
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Tidskriftsartikel (refereegranskat)abstract
- Based on the proposition that the relationship between a coach and athlete is at its best when both parties contribute to enhancing its quality, the present study sought to investigate if Shared Reality Theory could provide new insights on the topic. Specifically, the purpose of the present study was to explore: (a) how a shared reality is established, or fails to be established, over the course of the sporting partnership between athletes and their coach; and (b) how the presence of a shared reality (or not) in the coach-athlete relationship is related to the experienced quality of the relationship between athletes and their coach, as recorded over time. Narrative inquiry, embedded within a longitudinal qualitative approach, was adopted. Six female elite junior swimmers and their head coach completing three interviews each over a 9-month period. Data were analysed using narrative thematic analysis, leading to the development of two narratives: A prevention-oriented narrative and a promotion-oriented narrative. Overall, the findings suggests that athletes who experience a shared reality with their coach are more motivated and report a higher sense of psychological well-being. To establish the experience of a shared reality, reciprocal and honest communication motivated by trust in the other is needed. Due to power imbalance, it is deemed important for coaches to be supportive and trustworthy to encourage athletes to communicate with them, so the coach and his/her athletes can work together in a synergistic manner.
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