1. |
- Aggestam, Lena, et al.
(author)
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The Development and Evaluation of an Animated Video for Pre- and Postoperative Instructions for Patients with Osteoarthritis : A Design Science Research Approach
- 2024
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In: Geriatrics. - 2308-3417. ; 9:19, s. 1-11
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Journal article (peer-reviewed)abstract
- Osteoarthritis (OA) is a condition in the hip or knee joints that develops during a long period of time and sometimes needs hip or knee joint replacement surgery when pain gets too intense for the patient. This paper describes how an animated video for pre- and postoperative instructions for patients with osteoarthritis was designed. The design science research (DSR) approach was followed by creating a web-based animated video. The web-based animated video is used to support surgical departments with education for patients suffering from OA. In the web-based animated video, information about OA surgical treatment and its pre- and post-arrangements was included. The relevance, the rigor, and the design cycles were focused on, with some iterations of and improvements in the animations. Even after implementation, there was a feedback-loop with comments from the surgeons and their patients. Moreover, as more departments will use the web-based animated video, they want to make their special mark on it, so that further changes will be made. This paper presents the design and successful implementation of an animated video for pre- and postoperative instructions for patients with osteoarthritis, tightly linked to the patient journey and the workflow of healthcare professionals. The animated video serves not only as a tool to improve care but also as a basis for further scientific research studies.
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2. |
- Arjomandi Rad, Mohammad
(author)
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Data-driven and real-time prediction models for iterative and simulation-driven design processes
- 2022
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Licentiate thesis (other academic/artistic)abstract
- The development of more complex products has increased dependency on virtual/digital models and emphasized the role of simulations as a means of validation before production. This level of dependency on digital models and simulation togetherwith the customization level and continuous requirement change leads to a large number of iterations in each stage of the product development process. This research, studies such group of products that have multidisciplinary, highly iterative, and simulation-driven design processes. It is shown that these high-level technical products, which are commonly outsourced to suppliers, commonly suffer from a long development lead time. The literature points to several research tracks including design automation and data-driven design with possible support. After studying the advantages and disadvantages of each track, a data-driven approachis chosen and studied through two case studies leading to two supporting tools that are expected to improve the development lead time in associated design processes. Feature extraction in CAD as a way to facilitate metamodeling is proposed as the first solution. This support uses the concept of the medial axis to find highly correlated features that can be used in regression models. As for the second supporting tool, an automated CAD script is used to produce a library of images associated with design variants. Dynamic relaxation is used to label each variant with its finite element solution output. Finally, the library is used to train a convolutions neural network that maps screenshots of CAD as input to finite element field answers as output. Both supporting tools can be used to create real-time prediction models in the early conceptual phases of the product development process to explore design space faster and reduce lead time and cost.
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3. |
- Barbari, Stephanie R., et al.
(author)
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Enhanced polymerase activity permits efficient synthesis by cancer-Associated DNA polymerase variants at low dNTP levels
- 2022
-
In: Nucleic Acids Research. - : Oxford University Press. - 0305-1048 .- 1362-4962. ; 50:14, s. 8023-8040
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Journal article (peer-reviewed)abstract
- Amino acid substitutions in the exonuclease domain of DNA polymerase (Pol) cause ultramutated tumors. Studies in model organisms suggested pathogenic mechanisms distinct from a simple loss of exonuclease. These mechanisms remain unclear for most recurrent Pol mutations. Particularly, the highly prevalent V411L variant remained a long-standing puzzle with no detectable mutator effect in yeast despite the unequivocal association with ultramutation in cancers. Using purified four-subunit yeast Pol, we assessed the consequences of substitutions mimicking human V411L, S459F, F367S, L424V and D275V. While the effects on exonuclease activity vary widely, all common cancer-Associated variants have increased DNA polymerase activity. Notably, the analog of Pol-V411L is among the strongest polymerases, and structural analysis suggests defective polymerase-To-exonuclease site switching. We further show that the V411L analog produces a robust mutator phenotype in strains that lack mismatch repair, indicating a high rate of replication errors. Lastly, unlike wild-Type and exonuclease-dead Pol, hyperactive variants efficiently synthesize DNA at low dNTP concentrations. We propose that this characteristic could promote cancer cell survival and preferential participation of mutator polymerases in replication during metabolic stress. Our results support the notion that polymerase fitness, rather than low fidelity alone, is an important determinant of variant pathogenicity.
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4. |
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5. |
- Biswas, Rahul, et al.
(author)
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Two c's in a pod : cosmology-independent measurement of the Type Ia supernova colour-luminosity relation with a sibling pair
- 2022
-
In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 509:4, s. 5340-5356
-
Journal article (peer-reviewed)abstract
- Using Zwicky Transient Facility (ZTF) observations, we identify a pair of ‘sibling’ Type Ia supernovae (SNe Ia), i.e. hosted by the same galaxy at z = 0.0541. They exploded within 200 d from each other at a separation of 0.6arcsec0.6arcsec corresponding to a projected distance of only 0.6 kpc. Performing SALT2 light-curve fits to the gri ZTF photometry, we show that for these equally distant ‘standardizable candles’, there is a difference of 2 mag in their rest-frame B-band peaks, and the fainter supernova (SN) has a significantly red SALT2 colour c = 0.57 ± 0.04, while the stretch values x1 of the two SNe are similar, suggesting that the fainter SN is attenuated by dust in the interstellar medium of the host galaxy. We use these measurements to infer the SALT2 colour standardization parameter, β = 3.5 ± 0.3, independent of the underlying cosmology and Malmquist bias. Assuming the colour excess is entirely due to dust, the result differs by 2σ from the average Milky Way total-to-selective extinction ratio, but is in good agreement with the colour–brightness corrections empirically derived from the most recent SN Ia Hubble–Lemaitre diagram fits. Thus we suggest that SN ‘siblings’, which will increasingly be discovered in the coming years, can be used to probe the validity of the colour and light-curve shape corrections using in SN Ia cosmology while avoiding important systematic effects in their inference from global multiparameter fits to inhomogeneous data sets, and also help constrain the role of interstellar dust in SN Ia cosmology.
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6. |
- Borenäs, Marcus, et al.
(author)
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ALK signaling primes the DNA damage response sensitizing ALK-driven neuroblastoma to therapeutic ATR inhibition
- 2024
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In: Proceedings of the National Academy of Sciences of the United States of America. - 1091-6490. ; 121:1
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Journal article (peer-reviewed)abstract
- High-risk neuroblastoma (NB) is a significant clinical challenge. MYCN and Anaplastic Lymphoma Kinase (ALK), which are often involved in high-risk NB, lead to increased replication stress in cancer cells, suggesting therapeutic strategies. We previously identified an ATR (ataxia telangiectasia and Rad3-related)/ALK inhibitor (ATRi/ALKi) combination as such a strategy in two independent genetically modified mouse NB models. Here, we identify an underlying molecular mechanism, in which ALK signaling leads to phosphorylation of ATR and CHK1, supporting an effective DNA damage response. The importance of ALK inhibition is supported by mouse data, in which ATRi monotreatment resulted in a robust initial response, but subsequent relapse, in contrast to a 14-d ALKi/ATRi combination treatment that resulted in a robust and sustained response. Finally, we show that the remarkable response to the 14-d combined ATR/ALK inhibition protocol reflects a robust differentiation response, reprogramming tumor cells to a neuronal/Schwann cell lineage identity. Our results identify an ability of ATR inhibition to promote NB differentiation and underscore the importance of further exploring combined ALK/ATR inhibition in NB, particularly in high-risk patient groups with oncogene-induced replication stress.
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7. |
- Brennan, S. J., et al.
(author)
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Photometric and spectroscopic evolution of the interacting transient AT 2016jbu(Gaia16cfr)
- 2022
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In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 513:4, s. 5642-5665
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Journal article (peer-reviewed)abstract
- We present the results from a high-cadence, multiwavelength observation campaign of AT 2016jbu (aka Gaia16cfr), an interacting transient. This data set complements the current literature by adding higher cadence as well as extended coverage of the light-curve evolution and late-time spectroscopic evolution. Photometric coverage reveals that AT 2016jbu underwent significant photometric variability followed by two luminous events, the latter of which reached an absolute magnitude of MV ∼ −18.5 mag. This is similar to the transient SN 2009ip whose nature is still debated. Spectra are dominated by narrow emission lines and show a blue continuum during the peak of the second event. AT 2016jbu shows signatures of a complex, non-homogeneous circumstellar material (CSM). We see slowly evolving asymmetric hydrogen line profiles, with velocities of 500 km s−1 seen in narrow emission features from a slow-moving CSM, and up to 10 000 km s−1 seen in broad absorption from some high-velocity material. Late-time spectra (∼+1 yr) show a lack of forbidden emission lines expected from a core-collapse supernova and are dominated by strong emission from H, He I, and Ca II. Strong asymmetric emission features, a bumpy light curve, and continually evolving spectra suggest an inhibit nebular phase. We compare the evolution of H α among SN 2009ip-like transients and find possible evidence for orientation angle effects. The light-curve evolution of AT 2016jbu suggests similar, but not identical, circumstellar environments to other SN 2009ip-like transients.
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8. |
- Brennan, S. J., et al.
(author)
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Progenitor, environment, and modelling of the interacting transient AT 2016jbu (Gaia16cfr)
- 2022
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In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 513:4, s. 5666-5685
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Journal article (peer-reviewed)abstract
- We present the bolometric light curve, identification and analysis of the progenitor candidate, and preliminary modelling of AT 2016jbu (Gaia16cfr). We find a progenitor consistent with a ∼ 22–25 M⊙ yellow hypergiant surrounded by a dusty circumstellar shell, in agreement with what has been previously reported. We see evidence for significant photometric variability in the progenitor, as well as strong Hα emission consistent with pre-existing circumstellar material. The age of the environment, as well as the resolved stellar population surrounding AT 2016jbu, supports a progenitor age of >10 Myr, consistent with a progenitor mass of ∼22 M⊙. A joint analysis of the velocity evolution of AT 2016jbu and the photospheric radius inferred from the bolometric light curve shows the transient is consistent with two successive outbursts/explosions. The first outburst ejected material with velocity ∼650 km s−1, while the second, more energetic event ejected material at ∼4500 km s−1. Whether the latter is the core collapse of the progenitor remains uncertain. We place a limit on the ejected 56Ni mass of <0.016 M⊙. Using the Binary Population And Spectral Synthesis (BPASS) code, we explore a wide range of possible progenitor systems and find that the majority of these are in binaries, some of which are undergoing mass transfer or common-envelope evolution immediately prior to explosion. Finally, we use the SuperNova Explosion Code (SNEC) to demonstrate that the low-energy explosions within some of these binary systems, together with sufficient circumstellar material, can reproduce the overall morphology of the light curve of AT 2016jbu.
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9. |
- Camacho-Neves, Yssavo, et al.
(author)
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Over 500 Days in the Life of the Photosphere of the Type Iax Supernova SN 2014dt
- 2023
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In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 951:1
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Journal article (peer-reviewed)abstract
- Type Iax supernovae (SNe Iax) are the largest known class of peculiar white dwarf SNe, distinct from normal Type Ia supernovae (SNe Ia). The unique properties of SNe Iax, especially their strong photospheric lines out to extremely late times, allow us to model their optical spectra and derive the physical parameters of the long-lasting photosphere. We present an extensive spectral timeseries, including 21 new spectra, of SN Iax 2014dt from +11 to +562 days after maximum light. We are able to reproduce the entire timeseries with a self-consistent, nearly unaltered deflagration explosion model from Fink et al. using TARDIS, an open source radiative-transfer code. We find that the photospheric velocity of SN 2014dt slows its evolution between +64 and +148 days, which closely overlaps the phase when we see SN 2014dt diverge from the normal spectral evolution of SNe Ia (+90 to +150 days). The photospheric velocity at these epochs, ∼400–1000 km s−1, may demarcate a boundary within the ejecta below which the physics of SNe Iax and normal SNe Ia differ. Our results suggest that SN 2014dt is consistent with a weak deflagration explosion model that leaves behind a bound remnant and drives an optically thick, quasi-steady-state wind creating the photospheric lines at late times. The data also suggest that this wind may weaken at epochs past +450 days, perhaps indicating a radioactive power source that has decayed away.
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10. |
- Dhawan, Suhail, et al.
(author)
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A Uniform Type Ia Supernova Distance Ladder with the Zwicky Transient Facility : Absolute Calibration Based on the Tip of the Red Giant Branch Method
- 2022
-
In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 934:2
-
Journal article (peer-reviewed)abstract
- The current Cepheid-calibrated distance ladder measurement of H0 is reported to be in tension with the values inferred from the cosmic microwave background (CMB), assuming standard cosmology. However, some tip of the red giant branch (TRGB) estimates report H0 in better agreement with the CMB. Hence, it is critical to reduce systematic uncertainties in local measurements to understand the Hubble tension. In this paper, we propose a uniform distance ladder between the second and third rungs, combining Type Ia supernovae (SNe Ia) observed by the Zwicky Transient Facility (ZTF) with a TRGB calibration of their absolute luminosity. A large, volume-limited sample of both calibrator and Hubble flow SNe Ia from the same survey minimizes two of the largest sources of systematics: host-galaxy bias and nonuniform photometric calibration. We present results from a pilot study using the existing TRGB distance to the host galaxy of ZTF SN Ia SN 2021rhu (aka ZTF21abiuvdk) in NGC7814. Combining the ZTF calibrator with a volume-limited sample from the first data release of ZTF Hubble flow SNe Ia, we infer H0 = 76.94 ± 6.4 km s−1 Mpc−1, an 8.3% measurement. The error budget is dominated by the single object calibrating the SN Ia luminosity in this pilot study. However, the ZTF sample includes already five other SNe Ia within ∼20 Mpc for which TRGB distances can be obtained with the Hubble Space Telescope. Finally, we present the prospects of building this distance ladder out to 80 Mpc with James Webb Space Telescope observations of more than 100 ZTF SNe Ia.
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11. |
- Dhawan, Suhail, et al.
(author)
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Magnification, dust, and time-delay constraints from the first resolved strongly lensed Type Ia supernova iPTF16geu
- 2020
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In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 491:2, s. 2639-2654
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Journal article (peer-reviewed)abstract
- We report lensing magnifications, extinction, and time-delay estimates for the first resolved, multiply imaged Type Ia supernova iPTF16geu, at z = 0.409, using Hubble Space Telescope (HST) observations in combination with supporting ground-based data. Multiband photometry of the resolved images provides unique information about the differential dimming due to dust in the lensing galaxy. Using HST and Keck AO reference images taken after the SN faded, we obtain a total lensing magnification for iPTF16geu of mu = 67.8(-2.9)(+2.6), accounting for extinction in the host and lensing galaxy. As expected from the symmetry of the system, we measure very short time-delays for the three fainter images with respect to the brightest one: -0.23 +/- 0.99,-1.43 +/- 0.74, and 1.36 +/- 1.07 d. Interestingly, we find large differences between the magnifications of the four supernova images, even after accounting for uncertainties in the extinction corrections: Delta m(1) = -3.88(-0.06)(+0.07), Delta m(2) = -2.99(-0.08)(+0.09), Delta m(3) = -2.19(-0.15)(+0.14), and Delta m(4) = -2.40(-0.12)(+0.14) mag, discrepant with model predictions suggesting similar image brightnesses. A possible explanation for the large differences is gravitational lensing by substructures, micro- or millilensing, in addition to the large-scale lens causing the image separations. We find that the inferred magnification is insensitive to the assumptions about the dust properties in the host and lens galaxy.
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12. |
- Dhawan, Suhail, et al.
(author)
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The Zwicky Transient Facility Type Ia supernova survey : first data release and results
- 2022
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In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 510:2, s. 2228-2241
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Journal article (peer-reviewed)abstract
- Type Ia supernovae (SNe Ia) in the nearby Hubble flow are excellent distance indicators in cosmology. The Zwicky Transient Facility (ZTF) has observed a large sample of SNe from an untargeted, rolling survey, reaching 20.8, 20.6, and 20.3 mag in g r, and i band, respectively. With an FoV of 47 deg(2), ZTF discovered > 3000 SNe Ia in a little over 2.5 yr. Here, we report on the sample of 761 spectroscopically classified SNe Ia from the first year of operations (DR1). The sample has a median redshift (z) over bar = 0.057, nearly a factor of 2 higher than the current low-z sample. Our sample has a total of 934 spectra, of which 632 were obtained with the robotic SEDm on Palomar P60. We assess the potential for precision cosmology for a total of 305 SNe with redshifts from host galaxy spectra. The sample is already comparable in size to the entire combined literature low-z anchor sample. The median first detection is 13.5 d before maximum light, about 10 d earlier than the median in the literature. Furthermore, six SNe from our sample are at D-L < 80 Mpc, for which host galaxy distances can be obtained in the JAMES WEBB SPACE TELESCOPE era, such that we have calibrator and Hubble flow SNe observed with the same instrument. In the entire duration of ZTF-I, we have observed nearly 50 SNe for which we can obtain calibrator distances, key for per cent level distance scale measurements.
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13. |
- Diego, J. M., et al.
(author)
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Microlensing and the type Ia supernova iPTF16geu
- 2022
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 662
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Journal article (peer-reviewed)abstract
- The observed magnifications and light curves of the quadruply imaged iPTF16geu supernova (SN) offers a unique opportunity to study a lens system with a variety of independent constraints. The four observed positions can be used to constrain the macrolens model. The magnifications and light curves at the four SN positions are more useful to constrain microlensing models. We define the macrolens model as a combination of a baryonic component that traces the observed light distribution, and a dark matter halo component. We constrained the macrolens model using the positional constraints given by the four observed images, and compared it with the best model obtained when magnification constraints were included. We found that the magnification cannot be explained by a macrolens model alone, and that contributions from substructures such as microlenses are needed to explain the observed magnifications. We considered microlens models based on the inferred stellar mass from the baryonic component of the macrolens model, and used the observed magnification and light curves to constrain the contribution from microlenses. We computed the likelihood of a variety of macro and micro lens models where we varied the dark matter halo, baryonic component, and microlens configurations. We used information about the position, magnification, and, for the first time, the light curves of the four observed SN images. We combined macrolens and microlens models in order to reproduce the observations; the four SN positions, magnifications, and lack of fluctuations in the light curves. After marginalizing over the model parameters, we found that larger stellar surface mass densities are preferred. This result suggests that the mass of the baryonic component is dominated by its stellar component. We conclude that microlensing from the baryonic component suffices to explain the observed flux ratios and light curves.
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14. |
- Dimitriadis, Georgios, et al.
(author)
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SN 2021zny : an early flux excess combined with late-time oxygen emission suggests a double white dwarf merger event
- 2023
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In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 521:1, s. 1162-1183
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Journal article (peer-reviewed)abstract
- We present a photometric and spectroscopic analysis of the ultraluminous and slowly evolving 03fg-like Type Ia SN 2021zny. Our observational campaign starts from similar to 5.3 h after explosion (making SN 2021zny one of the earliest observed members of its class), with dense multiwavelength coverage from a variety of ground-and space-based telescopes, and is concluded with a nebular spectrum similar to 10 months after peak brightness. SN 2021zny displayed several characteristics of its class, such as the peak brightness (M-B = -19.95 mag), the slow decline (delta m(15)(B) = 0.62 mag), the blue early-time colours, the low ejecta velocities, and the presence of significant unburned material above the photosphere. However, a fluxexcess for the first similar to 1.5 d after explosion is observed in four photometric bands, making SN 2021zny the third 03fg-like event with this distinct behaviour, while its + 313 d spectrum shows prominent [OI] lines, a very unusual characteristic of thermonuclear SNe. The early flux excess can be explained as the outcome of the interaction of the ejecta with similar to 0 . 04 M-? of H/He-poor circumstellar material at a distance of similar to 10(12) cm, while the low ionization state of the late-time spectrum re veals lo w abundances of stable iron-peak elements. All our observations are in accordance with a progenitor system of two carbon/oxygen white dwarfs that undergo a merger event, with the disrupted white dwarf ejecting carbon-rich circumstellar material prior to the primary white dwarf detonation.
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15. |
- Dwomoh, Arianna M., et al.
(author)
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Evaluating the Consistency of Cosmological Distances Using Supernova Siblings in the Near-infrared
- 2024
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In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 965:1
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Journal article (peer-reviewed)abstract
- The study of supernova (SN) siblings, supernovae with the same host galaxy, is an important avenue for understanding and measuring the properties of Type Ia SN Ia light curves (LCs). Thus far, sibling analyses have mainly focused on optical LC data. Considering that LCs in the near-infrared (NIR) are expected to be better standard candles than those in the optical, we carry out the first analysis compiling SN siblings with only NIR data. We perform an extensive literature search of all SN siblings and find six sets of siblings with published NIR photometry. We calibrate each set of siblings ensuring they are on homogeneous photometric systems, fit the LCs with the SALT3-NIR and SNooPy models, and find median absolute differences in μ values between siblings of 0.248 and 0.186 mag, respectively. To evaluate the significance of these differences beyond measurement noise, we run simulations that mimic these LCs and provide an estimate for uncertainty on these median absolute differences of ∼0.052 mag, and we find that, statistically, our analysis rules out the nonexistence of intrinsic scatter in the NIR at the 99% level. When comparing the same sets of SN siblings, we observe a median absolute difference in μ values between siblings of 0.177 mag when using optical data alone as compared to 0.186 mag when using NIR data alone. It is unclear if these results may be due to limited statistics or poor quality NIR data, all of which will be improved with the Nancy Grace Roman Space Telescope.
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16. |
- Ekström, Lars, 1959, et al.
(author)
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A model for evaluation of the electric activity and oxygenation in the erector spinae muscle during isometric loading adapted for spine patients
- 2020
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In: Journal of Orthopaedic Surgery and Research. - : Springer Science and Business Media LLC. - 1749-799X. ; 15:1
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Journal article (peer-reviewed)abstract
- Background Simultaneous measurement of electromyography (EMG) and local muscle oxygenation is proposed in an isometric loading model adjusted for patients that have undergone spinal surgery. Methods Twelve patients with degenerative lumbar spinal stenosis (DLSS) were included. They were subjected to a test protocol before and after surgery. The protocol consisted of two parts, a dynamic and an isometric Ito loading with a time frame of 60 s and accompanying rest of 120 s. The Ito test was repeated three times. EMG was measured bilaterally at the L4 level and L2 and was recorded using surface electrodes and collected (Biopac Systems Inc.). EMG signal was expressed as RMS and median frequency (MF). Muscle tissue oxygen saturation (MrSO(2)) was monitored using a near-infrared spectroscopy (NIRS) device (INVOS (R) 5100C Oxymeter). Two NIRS sensors were positioned bilaterally at the L4 level. The intensity of the leg and back pain and perceived exertion before, during, and after the test was evaluated with a visual analogue scale (VAS) and Borg RPE-scale, respectively. Results All patients were able to perform and complete the test protocol pre- and postoperatively. A consistency of lower median and range values was noted in the sensors of EMG1 (15.3 mu V, range 4.5-30.7 mu V) and EMG2 (13.6 mu V, range 4.0-46.5 mu V) that were positioned lateral to NIRS sensors at L4 compared with EMG3 (18.9 mu V, range 6.5-50.0 mu V) and EMG4 (20.4 mu V, range 7.5-49.0 mu V) at L2. Right and left side of the erector spinae exhibited a similar electrical activity behaviour over time during Ito test (60 s). Regional MrSO(2) decreased over time during loading and returned to the baseline level during recovery on both left and right side. Both low back and leg pain was significantly reduced postoperatively. Conclusion Simultaneous measurement of surface EMG and NIRS seems to be a promising tool for objective assessment of paraspinal muscle function in terms of muscular activity and local muscle oxygenation changes in response to isometric trunk extension in patients that have undergone laminectomy for spinal stenosis.
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17. |
- Elgh, Fredrik, 1971-, et al.
(author)
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Traceability in engineer-to-order businesses
- 2020
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In: Systems engineering in research and industrial practice. - Cham : Springer. - 9783030333119 - 9783030333126 ; , s. 115-145
-
Book chapter (peer-reviewed)abstract
- A rapidly growing strategy in product design and manufacture, with great potential to improve customer value, is mass-customization. The main idea is to divide the product into modules that can be shared among different product variants. This will support a wide range of options for the end customer to select among, while an internal efficiency, similar to mass-production, can be achieved. This has been a success for many companies acting on the consumer market. However, many manufacturing companies are engineer-to-order (ETO) oriented, such as original equipment suppliers (OES). They design a unique solution, often in close collaboration with other companies. The solution can then be manufactured in different quantities depending on the client’s need. For these companies, there is a strategic need for developing high quality engineering support to further utilize and exploit the information and knowledge produced during product development and to succeed with a strategy influenced by the principles of mass-customization. This has to include the implementation and management of systems enabling highly custom-engineered products to be efficiently designed and manufactured. One challenge when introducing such flexible support is to enable traceability of decisions taken, tasks executed, knowledge used and artefacts developed throughout the whole lifecycle of an individual product. In this chapter, it is shown that traceability can be achieved by introducing support for capturing, structuring and mapping between decisions and resulting outputs, such as geometrical building blocks, knowledge implemented as rules, and the argumentation for the selection, design and specification of these. Three examples are presented where the concept Design Description has been modelled based on an item-oriented, a task-oriented, and a decision-oriented perspective which show the generality of the Design Description concept. The three examples demonstrate how to use the Design Description to enable traceability in platform design, product design, and manufacturing development processes.
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18. |
- Galbany, L., et al.
(author)
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An updated measurement of the Hubble constant from near-infrared observations of Type Ia supernovae
- 2023
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In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 679
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Journal article (peer-reviewed)abstract
- We present a measurement of the Hubble constant (H0) using type Ia supernovae (SNe Ia) in the near-infrared (NIR) from the recently updated sample of SNe Ia in nearby galaxies with distances measured via Cepheid period-luminosity relations by the SH0ES project. We collected public near-infrared photometry of up to 19 calibrator SNe Ia and 57 SNe Ia in the Hubble flow (z > 0.01), and directly measured their peak magnitudes in the J- and H-band by Gaussian processes and spline interpolation. Calibrator peak magnitudes together with Cepheid-based distances were used to estimate the average absolute magnitude in each band, while Hubble-flow SNe were used to constrain the zero-point intercept of the magnitude–redshift relation. Our baseline result of H0 is 72.3 ± 1.4 (stat) ±1.4 (syst) km s−1 Mpc−1 in the J-band and 72.3 ± 1.3 (stat) ±1.4 (syst) km s−1 Mpc−1 in the H-band, where the systematic uncertainties include the standard deviation of up to 21 variations of the analysis, the 0.7% distance scale systematic from SH0ES Cepheid anchors, a photometric zero-point systematic, and a cosmic variance systematic. Our final measurement represents a measurement with a precision of 2.8% in both bands. Among all the analysis variants, the largest change in H0 comes from limiting the sample to those SNe from the CSP and CfA programs; they are noteworthy because they are the best calibrated, yielding H0 ∼ 75 km s−1 Mpc−1 in both bands. We explore applying stretch and reddening corrections to standardize SN Ia NIR peak magnitudes, and we demonstrate that they are still useful to reduce the absolute magnitude scatter and, which improves its standardization, at least up to the H-band. Based on our results, in order to improve the precision of the H0 measurement with SNe Ia in the NIR in the future, we would need to increase the number of calibrator SNe Ia, to be able to extend the Hubble–Lemaître diagram to higher redshift, and to include standardization procedures to help reduce the NIR intrinsic scatter.
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19. |
- Goobar, Ariel, 1962-, et al.
(author)
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Uncovering a population of gravitational lens galaxies with magnified standard candle SN Zwicky
- 2023
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In: Nature Astronomy. - 2397-3366. ; 7:9, s. 1098-1107
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Journal article (peer-reviewed)abstract
- Detecting gravitationally lensed supernovae is among the biggest challenges in astronomy. It involves a combination of two very rare phenomena: catching the transient signal of a stellar explosion in a distant galaxy and observing it through a nearly perfectly aligned foreground galaxy that deflects light towards the observer. Here we describe how high-cadence optical observations with the Zwicky Transient Facility, with its unparalleled large field of view, led to the detection of a multiply imaged type Ia supernova, SN Zwicky, also known as SN 2022qmx. Magnified nearly 25-fold, the system was found thanks to the standard candle nature of type Ia supernovae. High-spatial-resolution imaging with the Keck telescope resolved four images of the supernova with very small angular separation, corresponding to an Einstein radius of only θE = 0.167″ and almost identical arrival times. The small θE and faintness of the lensing galaxy are very unusual, highlighting the importance of supernovae to fully characterize the properties of galaxy-scale gravitational lenses, including the impact of galaxy substructures.
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20. |
- Guglielmo, Priscilla, et al.
(author)
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Validation of automated whole-body analysis of metabolic and morphological parameters from an integrated FDG-PET/MRI acquisition
- 2020
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In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10:1
-
Journal article (peer-reviewed)abstract
- Automated quantification of tissue morphology and tracer uptake in PET/MR images could streamline the analysis compared to traditional manual methods. To validate a single atlas image segmentation approach for automated assessment of tissue volume, fat content (FF) and glucose uptake (GU) from whole-body [18F]FDG-PET/MR images. Twelve subjects underwent whole-body [18F]FDG-PET/MRI during hyperinsulinemic-euglycemic clamp. Automated analysis of tissue volumes, FF and GU were achieved using image registration to a single atlas image with reference segmentations of 18 volume of interests (VOIs). Manual segmentations by an experienced radiologist were used as reference. Quantification accuracy was assessed with Dice scores, group comparisons and correlations. VOI Dice scores ranged from 0.93 to 0.32. Muscles, brain, VAT and liver showed the highest scores. Pancreas, large and small intestines demonstrated lower segmentation accuracy and poor correlations. Estimated tissue volumes differed significantly in 8 cases. Tissue FFs were often slightly but significantly overestimated. Satisfactory agreements were observed in most tissue GUs. Automated tissue identification and characterization using a single atlas segmentation performs well compared to manual segmentation in most tissues and will be valuable in future studies. In certain tissues, alternative quantification methods or improvements to the current approach is needed.
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21. |
- Halim, Adrianus, et al.
(author)
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Improvement of Working Conditions and Opinions of Mine Workers When Battery Electric Vehicles (BEVs) Are Used Instead of Diesel Machines — Results of Field Trial at the Kittilä Mine, Finland
- 2022
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In: Mining, Metallurgy & Exploration. - : Springer. - 2524-3462 .- 2524-3470. ; 39:2, s. 203-219
-
Journal article (peer-reviewed)abstract
- A major part of the European Union’s (EU) project Sustainable Intelligent Mining System (SIMS) is investigating the development of diesel-free/carbon-neutral underground mines in order to ensure sustainable underground mining in the future. Replacing diesel machines with electric vehicles in underground hard rock mines has been widely acknowledged by the mining industry worldwide as a critical step to improve working conditions by reducing diesel exhaust related contaminants, to reduce mine ventilation electrical power cost by reducing mine airflow quantity, and to reduce mine greenhouse gas emissions. All of these are major requirements to achieve sustainable future underground mining practices. A field trial of Epiroc’s 2nd generation of Battery Electric Vehicles (BEVs) at Agnico Eagle Finland’s Kittilä mine was conducted during 2019 – 2020. Vehicles tested were MT42 mine truck, ST14 Load-Haul-Dump (LHD), and Boomer E2 jumbo drill rig. This paper outlines the improvement of the working conditions observed in the field trial, and the opinions of the mine personnel at Kittilä mine on using BEVs instead of diesel machines. Measurements of atmospheric contaminants and air temperatures taken during the field trial clearly demonstrated a significant improvement of working conditions when BEVs were operating as opposed to diesel machines. This field observation was supported by the opinion of the majority of the Kittilä mine workers. However, some remaining concerns must be addressed before BEVs can replace diesel machines.
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22. |
- Heikkinen, Tim, et al.
(author)
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Multidisciplinary design automation – A conceptual framework for working with product model extensions
- 2020
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In: International Journal of Agile Systems and Management. - : InderScience Publishers. - 1741-9174 .- 1741-9182. ; 13:1, s. 28-47
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Journal article (peer-reviewed)abstract
- Design automation can be used to support efficient information handling and knowledge processing in computer-based product modelling, as well as make possible new design exploration and optimisation capabilities. To be able to utilise and manage design automation systems over time, it is important to understand how the disciplinary methods and models are dependent on each other through the product model constituents and then how these relations should be built to support maintenance, leveraging and future reuse. Awareness of the concrete representation of relations could support the system's traceability and transparency, and depending on the chosen technique, comprehension and extendability can be affected. This paper presents a conceptual framework for how a set of product model constituents are, can and to some extent, should be extended to define relations in multidisciplinary design automation systems.
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23. |
- Holmberg, Jonas, 1976-
(author)
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High volumetric machining strategies for superalloy gasturbine components : Comparing conventional and nonconventional machining methods for efficient manufacturing
- 2020
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Doctoral thesis (other academic/artistic)abstract
- There is a strong industrial driving force to find alternative manufacturing technologies in order to make the production of aero engine components of superalloys even more efficient than it is today. Introducing new and nonconventional machining technologies, as well as enhanced utilisation of today's high volumetric manufacturing, allows taking a leap to increase the material removal rate and the productivity. However, the final goal is to meet there quirements set for today's machined surfaces.The objective with the present work has been performed to show how the conventional, Milling, and the non-conventional machining methods, Abrasive Water Jet Machining, AWJM, Laser Beam Machining, LBM, and Electrical Discharge Machining, EDM, affect the surface integrity. This knowledge can beused to define and optimise different manufacturing alternatives for existing orfuture production.The results show that it is possible to use the rough milling to a greater extent if the impact on residuals stresses and deformation is used when determine the machining allowance. This could have a great impact on the productivity. However, further improvement of the productivity requires an alternative method. For this reason, EDM and AWJM was evaluated and shown to be suitable alternatives to today's manufacturing methods, but both methods require post processing. The results showed that a combination of two post processes is required for addressing issues with residue, topography and residual stresses.The most promising and effective manufacturing strategy would be EDM or AWJM for rough machining followed by post processing either by finish millingor post processing by means of High-Pressure Water Jet Cleaning and shot peening. If EDM and AWJM are to be considered as finish machining operations, further development of the two methods are required.
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24. |
- Jencson, Jacob E., et al.
(author)
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AT 2019qyl in NGC 300 : Internal Collisions in the Early Outflow from a Very Fast Nova in a Symbiotic Binary
- 2021
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In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 920:2
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Journal article (peer-reviewed)abstract
- Nova eruptions, thermonuclear explosions on the surfaces of white dwarfs (WDs), are now recognized to be among the most common shock-powered astrophysical transients. We present the early discovery and rapid ultraviolet (UV), optical, and infrared (IR) temporal development of AT 2019qyl, a recent nova in the nearby Sculptor Group galaxy NGC 300. The light curve shows a rapid rise lasting ≲1 day, reaching a peak absolute magnitude of MV = −9.2 mag and a very fast decline, fading by 2 mag over 3.5 days. A steep dropoff in the light curves after 71 days and the rapid decline timescale suggest a low-mass ejection from a massive WD with MWD ≳ 1.2 M⊙. We present an unprecedented view of the early spectroscopic evolution of such an event. Three spectra prior to the peak reveal a complex, multicomponent outflow giving rise to internal collisions and shocks in the ejecta of an He/N-class nova. We identify a coincident IR-variable counterpart in the extensive preeruption coverage of the transient location and infer the presence of a symbiotic progenitor system with an O-rich asymptotic-giant-branch donor star, as well as evidence for an earlier UV-bright outburst in 2014. We suggest that AT 2019qyl is analogous to the subset of Galactic recurrent novae with red-giant companions such as RS Oph and other embedded nova systems like V407 Cyg. Our observations provide new evidence that internal shocks between multiple, distinct outflow components likely contribute to the generation of the shock-powered emission from such systems.
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25. |
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26. |
- Johansson, Joel, et al.
(author)
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Incidence of Appendiceal Malignancies in Sweden Between 1970 and 2012
- 2020
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In: World Journal of Surgery. - : SPRINGER. - 0364-2313 .- 1432-2323. ; 44, s. 4086-4092
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Journal article (peer-reviewed)abstract
- Background There is limited knowledge about the epidemiology of the major histological subtypes of appendiceal malignancy: adenocarcinoma and neuroendocrine neoplasm of the appendix (A-NEN). The aims of this national cohort study were to assess the prevalence, incidence and trends of appendiceal malignancies in Sweden. Method All individuals who underwent appendicectomy and all diagnosed with appendiceal malignancy from 1970 to 2012 were identified from the National Patient Register and the Swedish Cancer Registry. Demographic data of the background population were obtained from Statistics Sweden. The incidence rate (IR) and the prevalence of appendiceal malignancy per performed appendicectomy were calculated. Results We identified 3774 patients with appendiceal malignancy. IR of A-NEN was 5.8/10(6)person-years with a peak of 8.4/10(6)at age 20-30 years, whereafter it plateaued at a somewhat lower level. IR for adenocarcinoma was 3.7/10(6)person-years, starting at a very low level among the youngest and increasing to 15.4/10(6)at age 80-89 years. The IR of adenocarcinoma increased from 2.6/10(6)in 1970-1979 to 5.4/10(6)in 2010-2012. The IR of A-NEN was stable during the study period. The prevalence per appendicectomy was low for both types of malignancies among the young but increased with age, most dramatically for adenocarcinoma. There was a trend during the study period towards more extensive surgery. Conclusion Adenocarcinoma is most common and increasing in the elderly, whereas A-NEN affects all ages with a peak in young age. This peak probably reflects removal of occult A-NEN due to the higher appendicectomy frequency in the young.
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27. |
- Johansson, Joel, et al.
(author)
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Spectroscopy of the first resolved strongly lensed Type Ia supernova iPTF16geu
- 2021
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In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 502:1, s. 510-520
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Journal article (peer-reviewed)abstract
- We report the results from spectroscopic observations of the multiple images of the strongly lensed Type Ia supernova (SN Ia), iPTF16geu, obtained with ground-based telescopes and the Hubble Space Telescope (HST). From a single epoch of slitless spectroscopy with HST, we resolve spectra of individual lensed supernova images for the first time. This allows us to perform an independent measurement of the time-delay between the two brightest images, Delta t = 1.4 +/- 5.0 d, which is consistent with the time-delay measured from the light curves. We also present measurements of narrow emission and absorption lines characterizing the interstellar medium in the SN Ia host galaxy at z = 0.4087, as well as in the foreground lensing galaxy at z = 0.2163. We detect strong Naid absorption in the host galaxy, indicating that iPTF16geu belongs to a subclass of SNe Ia displaying 'anomalously' large Naid column densities compared to dust extinction derived from light curves. For the lens galaxy, we refine the measurement of the velocity dispersion, sigma = 129 +/- 4 kms(-1), which significantly constrains the lens model. We use ground-based spectroscopy, boosted by a factor similar to 70 from lensing magnification, to study the properties of a high-z SN Ia with unprecedented signal-to-noise ratio. The spectral properties of the supernova, such as pseudo-Equivalent widths of several absorption features and velocities of the Si II-line, indicate that iPTF16geu is a normal SN Ia. We do not detect any significant deviations of the SN spectral energy distribution from microlensing of the SN photosphere by stars and compact objects in the lensing galaxy.
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28. |
- Johansson, Mikael, 1982-, et al.
(author)
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Evaluation of test results and ranking criteria for Varestraint testing of an austenitic high-temperature alloy
- 2020
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In: Welding in the World. - : Springer Science and Business Media LLC. - 0043-2288 .- 1878-6669. ; 64, s. 903-912
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Journal article (peer-reviewed)abstract
- Varestraint testing is commonly used to evaluate hot cracking susceptibility of materials. In this paper, the dependence of operators and evaluation technique on test results is studied for a high-temperature austenitic stainless steel (UNS S31035). Samples were tested at six different strain levels ranging from 0.7 to 3.8%. Four different operators evaluated the same samples following the same instructions on how to measure the cracks manually in an optical microscope at x 25 magnification. The largest variation among operators evaluation was found for low strain levels where small and few cracks were found. In addition, one of the four operators used image analysis to evaluate the samples at x 50 magnification. The average total crack length and total number of cracks in fusion zone and heat-affected zone were approximately 1.5 times higher when using image analysis compared with manual evaluation. Image analysis at x 50 made it possible to detect smaller cracks compared with manual evaluation at x 25 magnification, contributing to an increased number of cracks detected. The maximum crack length using image analysis at x 50 was similar to manual evaluation made at x 25 magnification and was the criterion that showed the least variation in this study. However, further comparisons using other magnifications are needed to verify the agreement between manual evaluation and image analysis found in this study. An advantage with evaluation using image analysis is that it provides traceable results. A harmonized standard for Varestraint testing, and especially for evaluation, would decrease the variation among operators and laboratories.
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29. |
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30. |
- Kool, Erik C., et al.
(author)
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A radio-detected type Ia supernova with helium-rich circumstellar material
- 2023
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In: Nature. - 0028-0836 .- 1476-4687. ; 617:7961, s. 477-482
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Journal article (peer-reviewed)abstract
- Type Ia supernovae (SNe Ia) are thermonuclear explosions of degenerate white dwarf stars destabilized by mass accretion from a companion star1, but the nature of their progenitors remains poorly understood. A way to discriminate between progenitor systems is through radio observations; a non-degenerate companion star is expected to lose material through winds2 or binary interaction3 before explosion, and the supernova ejecta crashing into this nearby circumstellar material should result in radio synchrotron emission. However, despite extensive efforts, no type Ia supernova (SN Ia) has ever been detected at radio wavelengths, which suggests a clean environment and a companion star that is itself a degenerate white dwarf star4,5. Here we report on the study of SN 2020eyj, a SN Ia showing helium-rich circumstellar material, as demonstrated by its spectral features, infrared emission and, for the first time in a SN Ia to our knowledge, a radio counterpart. On the basis of our modelling, we conclude that the circumstellar material probably originates from a single-degenerate binary system in which a white dwarf accretes material from a helium donor star, an often proposed formation channel for SNe Ia (refs. 6,7). We describe how comprehensive radio follow-up of SN 2020eyj-like SNe Ia can improve the constraints on their progenitor systems.
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31. |
- Kwok, Lindsey A., et al.
(author)
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A JWST Near- and Mid-infrared Nebular Spectrum of the Type Ia Supernova 2021aefx
- 2023
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In: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8205 .- 2041-8213. ; 944:1
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Journal article (peer-reviewed)abstract
- We present JWST near-infrared (NIR) and mid-infrared (MIR) spectroscopic observations of the nearby normal Type Ia supernova (SN) SN 2021aefx in the nebular phase at +255 days past maximum light. Our Near Infrared Spectrograph (NIRSpec) and Mid Infrared Instrument observations, combined with ground-based optical data from the South African Large Telescope, constitute the first complete optical+NIR+MIR nebular SN Ia spectrum covering 0.3–14 μm. This spectrum unveils the previously unobserved 2.5−5 μm region, revealing strong nebular iron and stable nickel emission, indicative of high-density burning that can constrain the progenitor mass. The data show a significant improvement in sensitivity and resolution compared to previous Spitzer MIR data. We identify numerous NIR and MIR nebular emission lines from iron-group elements as well as lines from the intermediate-mass element argon. The argon lines extend to higher velocities than the iron-group elements, suggesting stratified ejecta that are a hallmark of delayed-detonation or double-detonation SN Ia models. We present fits to simple geometric line profiles to features beyond 1.2 μm and find that most lines are consistent with Gaussian or spherical emission distributions, while the [Ar iii] 8.99 μm line has a distinctively flat-topped profile indicating a thick spherical shell of emission. Using our line profile fits, we investigate the emissivity structure of SN 2021aefx and measure kinematic properties. Continued observations of SN 2021aefx and other SNe Ia with JWST will be transformative to the study of SN Ia composition, ionization structure, density, and temperature, and will provide important constraints on SN Ia progenitor and explosion models.
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32. |
- Kwok, Lindsey A., et al.
(author)
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Ground-based and JWST Observations of SN 2022pul. II. Evidence from Nebular Spectroscopy for a Violent Merger in a Peculiar Type Ia Supernova
- 2024
-
In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 966:1
-
Journal article (peer-reviewed)abstract
- We present an analysis of ground-based and JWST observations of SN 2022pul, a peculiar "03fg-like" (or "super-Chandrasekhar") Type Ia supernova (SN Ia), in the nebular phase at 338 days postexplosion. Our combined spectrum continuously covers 0.4–14 μm and includes the first mid-infrared spectrum of a 03fg-like SN Ia. Compared to normal SN Ia 2021aefx, SN 2022pul exhibits a lower mean ionization state, asymmetric emission-line profiles, stronger emission from the intermediate-mass elements (IMEs) argon and calcium, weaker emission from iron-group elements (IGEs), and the first unambiguous detection of neon in a SN Ia. A strong, broad, centrally peaked [Ne ii] line at 12.81 μm was previously predicted as a hallmark of "violent merger" SN Ia models, where dynamical interaction between two sub-MCh white dwarfs (WDs) causes disruption of the lower-mass WD and detonation of the other. The violent merger scenario was already a leading hypothesis for 03fg-like SNe Ia; in SN 2022pul it can explain the large-scale ejecta asymmetries seen between the IMEs and IGEs and the central location of narrow oxygen and broad neon. We modify extant models to add clumping of the ejecta to reproduce the optical iron emission better, and add mass in the innermost region (<2000 km s−1) to account for the observed narrow [O i] λλ6300, 6364 emission. A violent WD–WD merger explains many of the observations of SN 2022pul, and our results favor this model interpretation for the subclass of 03fg-like SNe Ia.
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33. |
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34. |
- Lind, Lars, et al.
(author)
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Comparison of four non-alcoholic fatty liver disease detection scores in a Caucasian population
- 2020
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In: World Journal of Hepatology. - : Baishideng Publishing Group Inc.. - 1948-5182. ; 12:4, s. 149-159
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Journal article (peer-reviewed)abstract
- BACKGROUNDNon-alcoholic fatty liver disease (NAFLD) is a common disorder, with an estimated prevalence ranging from 20% to 35% in the general population. Several scores based on easily measurable biochemical and clinical parameters, including the fatty liver index (FLI), hepatic steatosis index (HSI), lipid accumulation product (LAP), and NAFLD liver fat score (LFS), have been developed for the detection of NAFLD. However, comparative information regarding the efficacy of these scores for predicting NAFLD in population-based samples comprising normal and high-risk individuals is lacking.AIMTo evaluate four NAFLD detection scores in two samples with different NAFLD risks.METHODSNAFLD screening was performed in a population-based sample of 50-year-old individuals in Uppsala, Sweden [n = 310; Prospective investigation of obesity, energy and metabolism (POEM) study] and a high-risk population comprising patients with a body mass index > 25 kg/m2 and either high plasma triglycerides (≥ 1.7 mmol/L) or type 2 diabetes (n = 310; EFFECT studies). NAFLD was defined as liver fat > 5.5% using magnetic resonance imaging-proton density fat fraction. FLI, HSI, LAP, and NAFLD LFS were assessed. A logistic regression model was used to evaluate the effectiveness of the different scores.RESULTSThe prevalence of NAFLD was 23% in POEM. FLI showed the highest receiver operating characteristic area under the curve (ROC AUC; 0.82) and was significantly better than the LAP score (P = 0.005 vs LAP, P = 0.08 vs LFS, P = 0.12 vs HSI) for detection of NAFLD. The other three indices performed equally in POEM (0.77-0.78). The prevalence of NAFLD was 74% in EFFECT; LFS performed best (ROC AUC 0.80) in this sample. The ROC AUC for LFS (0.80) was significantly higher than that for FLI (P = 0.0019) and LAP (P = 0.0022), but not HSI (P = 0.11). We performed a sensitivity analysis with stratification for the two high-risk subgroups (patients with diabetes or hypertriglyceridemia) from the EFFECT studies. LAP performed best in patients with hypertriglyceridemia. No major differences were observed between the other scores.CONCLUSIONThe four investigated NAFLD scores performed differently in the populationbased vs high-risk setting. FLI was preferable in the population-based setting, while LFS performed best in the high-risk setting.
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35. |
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36. |
- Lind, Lars, et al.
(author)
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The Plasma Metabolomic Profile is Differently Associated with Liver Fat, Visceral Adipose Tissue, and Pancreatic Fat
- 2021
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In: Journal of Clinical Endocrinology and Metabolism. - : Lippincott Williams & Wilkins. - 0021-972X .- 1945-7197. ; 106:1, s. e118-e129
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Journal article (peer-reviewed)abstract
- CONTEXT: Metabolic differences between ectopic fat depots may provide novel insights to obesity-related diseases.OBJECTIVE: To investigate the plasma metabolomic profiles in relation to visceral adipose tissue (VAT) volume and liver and pancreas fat percentages.DESIGN: Cross-sectional.SETTING: Multicenter at academic research laboratories.PATIENTS: Magnetic resonance imaging (MRI) was used to assess VAT volume, the percentage of fat in the liver and pancreas (proton density fat fraction [PDFF]) at baseline in 310 individuals with a body mass index ≥ 25 kg/m2 and with serum triglycerides ≥ 1.7 mmol/l and/or type 2 diabetes screened for inclusion in the 2 effect of omega-3 carboxylic acid on liver fat content studies.INTERVENTION: None.MAIN OUTCOME MEASURE: Metabolomic profiling with mass spectroscopy enabled the determination of 1063 plasma metabolites.RESULTS: Thirty metabolites were associated with VAT volume, 31 with liver PDFF, and 2 with pancreas PDFF when adjusting for age, sex, total body fat mass, and fasting glucose. Liver PDFF and VAT shared 4 metabolites, while the 2 metabolites related to pancreas PDFF were unique. The top metabolites associated with liver PDFF were palmitoyl-palmitoleoyl-GPC (16:0/16:1), dihydrosphingomyelin (d18:0/22:0), and betaine. The addition of these metabolites to the Liver Fat Score improved C-statistics significantly (from 0.776 to 0.861, P = 0.0004), regarding discrimination of liver steatosis.CONCLUSION: Liver PDFF and VAT adipose tissue shared several metabolic associations, while those were not shared with pancreatic PDFF, indicating partly distinct metabolic profiles associated with different ectopic fat depots. The addition of 3 metabolites to the Liver Fat Score improved the prediction of liver steatosis.
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37. |
- Liu, Chang, et al.
(author)
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SN 2022joj : A Peculiar Type Ia Supernova Possibly Driven by an Asymmetric Helium-shell Double Detonation
- 2023
-
In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 958:2
-
Journal article (peer-reviewed)abstract
- We present observations of SN 2022joj, a peculiar Type Ia supernova discovered by the Zwicky Transient Facility. SN 2022joj exhibits an unusually red g ZTF - r ZTF color at early times and a rapid blueward evolution afterward. Around maximum brightness, SN 2022joj shows a high luminosity ( MgZTF,max similar or equal to-19.7 mag), a blue broadband color (g ZTF - r ZTF similar or equal to -0.2 mag), and shallow Si ii absorption lines, consistent with those of overluminous, SN 1991T-like events. The maximum-light spectrum also shows prominent absorption around 4200 angstrom, which resembles the Ti ii features in subluminous, SN 1991bg-like events. Despite the blue optical-band colors, SN 2022joj exhibits extremely red ultraviolet minus optical colors at maximum luminosity (u - v similar or equal to 0.6 mag and uvw1 - v similar or equal to 2.5 mag), suggesting a suppression of flux at similar to 2500-4000 angstrom. Strong C ii lines are also detected at peak. We show that these unusual spectroscopic properties are broadly consistent with the helium-shell double detonation of a sub-Chandrasekhar mass (M similar or equal to 1 M circle dot) carbon/oxygen white dwarf from a relatively massive helium shell (M s similar or equal to 0.04-0.1 M circle dot), if observed along a line of sight roughly opposite to where the shell initially detonates. None of the existing models could quantitatively explain all the peculiarities observed in SN 2022joj. The low flux ratio of [Ni ii] lambda 7378 to [Fe ii] lambda 7155 emission in the late-time nebular spectra indicates a low yield of stable Ni isotopes, favoring a sub-Chandrasekhar mass progenitor. The significant blueshift measured in the [Fe ii] lambda 7155 line is also consistent with an asymmetric chemical distribution in the ejecta, as is predicted in double-detonation models.
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38. |
- Lund, Erik, et al.
(author)
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Mining 4.0 and its effects on work environment, competence, organisation and society – a scoping review
- 2024
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In: Mineral Economics. - : Springer Science and Business Media Deutschland GmbH. - 2191-2203 .- 2191-2211.
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Journal article (peer-reviewed)abstract
- The mining industry is facing a technological shift with Industry 4.0 creating new conditions for mining. This is often referred to as Mining 4.0. To succeed through the technological shift, the industry need to handle several challenges wisely, such as how to utilise the new digital technology to promote sustainable work environments, how to recruit skilled workers to the industry, and how to manage organisational challenges as a result of the technological shift. This scoping literature review examines a large field of literature on how Mining 4.0 might affect the mining industry in areas such as work environment, competences, organisation and society, and what can be done to promote sustainability going forward. The paper also identifies several areas that have not been explored in previous research. These include empirical studies on the effects of the technological shift brought about by Mining 4.0 on work environments, and how to attract younger generations to mining to ensure sustainability in the industry going forward.
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39. |
- Lund, Erik, et al.
(author)
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The Designers’ Perspective on Autonomous Mining Systems and Sociotechnology
- 2024
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In: Mining, Metallurgy and Exploration. - : Springer Science and Business Media Deutschland GmbH. - 2524-3462 .- 2524-3470. ; 41:2, s. 647-657
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Journal article (peer-reviewed)abstract
- Digitalization and automation technology offer new possibilities to increase productivity and obtain higher levels of autonomy in mining operations. Introducing autonomous systems into mining is not only a technical problem in terms of effectiveness and efficiency, nor a problem of safety in human-automation interactions. The systems also need to be designed and developed so that they foster healthy and attractive working environments. The design and development phase of new mining technology has not been extensively studied previously. To fill this knowledge gap, we investigated technology developers’ basic assumptions about humans and their interactions with the technology they develop. We conducted five semi-structured workshops within an EU funded project concerned with developing digitalization and automation solutions for the mining industry. The data suggests that many critical functions will still be under human control in future mining systems. The results also indicate increased complexity in the interaction between autonomous systems and humans as the technology becomes more advanced. As a result, we suggest that a human perspective, based on sociotechnical principles, should not only be considered in implementing the technology at mines but also in the early conceptual phases of developing and designing the technology. This will ensure healthy and attractive work environments in the future mining industry.
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40. |
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41. |
- Lööw, Joel, et al.
(author)
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A CHANGING WORK ENVIRONMENT IN THE WAKE OF THE COVID-19 PANDEMIC? – OBSERVATIONS FROM MANAGERS IN A SWEDISH MINING COMPANY
- 2023
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In: Occupational Safety and Hygiene – SHO2023 Proceedings Book. - : Portuguese Society of Occupational Safety and Hygiene (SPOSHO). - 9789895486342 ; , s. 376-389, s. 376-389
-
Conference paper (peer-reviewed)abstract
- Background: The Covid-19 pandemic has changed work life in many ways for many people; however, it is still an open question as to what changes will become permanent and what aspects of work life will return to that which was considered “normal” before the pandemic.Objective: In this study, the authors describe and analyse the effects of Covid-19 on managers in a large Swedish mining company.Method: This study is based on both quantitative and qualitative methods. Empirical material is used to explore the effects of the pandemic on the work environments of managers. Results are based on interviews in combination with a self-assessment process regarding how the managers allocated their work time during a work week.Results: The results describe the work activities of the studied managers supported with quotes from interview studies to illustrate to most central observations of how work has changed due to the Covid-19 pandemic.Conclusion: The results are summarized into six hypotheses: 1) the workday was densified due to remote meetings; 2) "double work" during meetings was the rule, rather than the exception; 3) meetings became more focused; 4) meetings became more accessible; 5) the manager became less operational; and 6) a new work culture was created.Application: This is an exploratory study of consequences and effects of Covid-19 pandemic summarized in six hypotheses that can befruitful for further and future studies.
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42. |
- Lööw, Joel
(author)
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'Soft' Questions in a 'Hard' Industry? : Sociotechnical Problems of the Mining Industry
- 2020
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Doctoral thesis (other academic/artistic)abstract
- The workplaces of mining industry fail to attract the skills and competences that the industry needs for maintaining its production and, in particular, tackling its future challenges. Some of the challenges that face the mining industry are technical and call for technical solutions: deeper and poorer ore deposits, greater environmental requirements, and lower ore prices, for example. Other challenges are social: the mining industry must secure its social licence to operate and, in particular, its current workforce is ageing at the same time as younger generations seem uninterested in employment in the industry. Yet, these technical and social—“hard” and “soft”— challenges relate in such a way that attempting to solve one question will depend on and be influenced by how other challenges are solved. This thesis argues that most of these challenges have a connection to the workplaces of the mining industry, such that the industry’s ability to provide attractive workplaces will significantly influence how it can overcome its other challenges—meaning, most challenges have social components and require social (soft) interventions as well as technical (hard) interventions. However, the mining industry approaches most of its challenges from a technical perspective and seeks to solve its problems with the help of technology; the workplaces of the mining industry do not have to be unattractive, but to make them attractive requires that the mining industry changes its approach to this question, so that the industry comes to treat the question as one of a sociotechnical process in which “hard” and “soft” issues are given equal attention. The purpose of this thesis is to outline such a process. The thesis seeks to develop an understanding of the interplay of social and technical matters in the mining industry and, through this, how workplaces and technology can be developed so that social and technical systems can come to harmonise.This thesis uses a theoretical framework based in the tradition of sociotechnical design but combines this with insights from social studies of technology, the “travel of ideas” literature and institutional pragmatism. This conceptualisation sees very little division between “hard” and “soft” questions and understands technology to be more than its physical artefacts; technology is the whole of the sociotechnical network that surrounds technology’s development, use and implementation. Technology, in this way, is best understood to be information, meaning that technology’s depiction (technology’s metaphors) has a important influence on final effects of technology. In extension, much can be understood about technology and its purposes (e.g., to improve the work environment) by treating technology as ideas and focusing how these ideas travel between different contexts. Such an analysis identifies the perspectives of individuals or actors, and how these perspectives differ, as important components in creating attractive workplaces in the mining industry. The empirical basis for this thesis comes from several projects conducted within and with the mining industry between 2014 and 2020. These projects have included investigations into how the mining industry has worked with safety, as well as the evaluation of work environment effects of new technology, and the providing recommendations for the development of new technology. These projects have entailed the use several different methods: interviews (including workshops) with technology developers, operators, work environment managers, and so on; document studies; and participant observations. The results of this thesis exemplify how technology and the design of workplaces in the mining industry can be conceptualised in the manner suggested by the theoretical framework, highlighting, for example, the constant presence of an interplay between technology and social matters, and how instrumental-rationalistic and institutional logic are present in both cases. The results also show that the way different actors understand technology has an important effect on workplace effects and whether these workplaces emerge as attractive or not. Thus, for technology to be able to address the lacking attractiveness of the mining industry’s workplaces—and in extension, for the mining industry to address its future challenges—requires technology to be developed and implemented using open, transparent, and participatory processes. This thesis contributes an understanding that harmonisation between technical and social systems (as understood in sociotechnical theory) depends on how different actors within these systems view technology, and that systems fail to harmonise when these views do not match. The thesis suggests, in this, that these views go beyond technical function and properties to include norms and values. Tackling the challenges of the mining industry requires rethinking and further developing participatory design and decision-making processes. There will be no one-fit-all solutions nor will single interventions be enough to address the mining industry’s challenges. Instead, the processes surrounding the development and implementation of technology need to further consider individual needs and desires, technical and otherwise; creating attractive workplaces in the mining industry is a humanistic and democratic undertaking.
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43. |
- Markgren, Joel, et al.
(author)
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Clustering and cross-linking of the wheat storage protein α-gliadin : A combined experimental and theoretical approach
- 2022
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In: International Journal of Biological Macromolecules. - : Elsevier BV. - 0141-8130 .- 1879-0003. ; 211, s. 592-615
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Journal article (peer-reviewed)abstract
- Our aim was to understand mechanisms for clustering and cross-linking of gliadins, a wheat seed storage protein type, monomeric in native state, but incorporated in network while processed. The mechanisms were studied utilizing spectroscopy and high-performance liquid chromatography on a gliadin-rich fraction, in vitro produced alpha-gliadins, and synthetic gliadin peptides, and by coarse-grained modelling, Monte Carlo simulations and prediction algorithms. In solution, gliadins with alpha-helix structures (dip at 205 nm in CD) were primarily present as monomeric molecules and clusters of gliadins (peaks at 650- and 700-s on SE-HPLC). At drying, large polymers (Rg 90.3 nm by DLS) were formed and 13-sheets increased (14% by FTIR). Trained algorithms predicted aggregation areas at amino acids 115-140, 150-179, and 250-268, and induction of liquid-liquid phase separation at P- and Poly-Q-sequences (Score = 1). Simulations showed that gliadins formed polymers by tail-to-tail or a hydrophobic core (Kratky plots and Ree = 35 and 60 for C- and N-terminal). Thus, the N-terminal formed clusters while the C-terminal formed aggregates by disulphide and lanthionine bonds, with favoured hydrophobic clustering of similar/exact peptide sections (synthetic peptide mixtures on SE-HPLC). Mechanisms of clustering and cross-linking of the gliadins presented here, contribute ability to tailor processing results, using these proteins.
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44. |
- Markgren, Joel, et al.
(author)
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Glutenin and Gliadin, a Piece in the Puzzle of their Structural Properties in the Cell Described through Monte Carlo Simulations
- 2020
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In: Biomolecules. - : MDPI. - 2218-273X. ; 10:8
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Journal article (peer-reviewed)abstract
- Gluten protein crosslinking is a predetermined process where specific intra- and intermolecular disulfide bonds differ depending on the protein and cysteine motif. In this article, all-atom Monte Carlo simulations were used to understand the formation of disulfide bonds in gliadins and low molecular weight glutenin subunits (LMW-GS). The two intrinsically disordered proteins appeared to contain mostly turns and loops and showed "self-avoiding walk" behavior in water. Cysteine residues involved in intramolecular disulfide bonds were located next to hydrophobic peptide sections in the primary sequence. Hydrophobicity of neighboring peptide sections, synthesis chronology, and amino acid chain flexibility were identified as important factors in securing the specificity of intramolecular disulfide bonds formed directly after synthesis. The two LMW-GS cysteine residues that form intermolecular disulfide bonds were positioned next to peptide sections of lower hydrophobicity, and these cysteine residues are more exposed to the cytosolic conditions, which influence the crosslinking behavior. In addition, coarse-grained Monte Carlo simulations revealed that the protein folding is independent of ionic strength. The potential molecular behavior associated with disulfide bonds, as reported here, increases the biological understanding of seed storage protein function and provides opportunities to tailor their functional properties for different applications.
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45. |
- Molnar, Malin, 1977-, et al.
(author)
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Facilitating and straining factors affecting the health and sustainability of young managers in a modern mining industry : Self-fulfilment and development - a buffer for young managers?
- 2023
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In: Arbetsliv i omvandling. - Lund : Lunds universitet. - 1404-8426. ; :2, s. 3-53
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Journal article (peer-reviewed)abstract
- To be able to attract, retain and develop talented individuals to managerial positions is important for organizations. Recently, however, there are indications that young professionals are reluctant to accept a leadership role. There is a lack of research exploring the reasons for this reluctance and investigating the working conditions and health of young managers; especially within heavy industries such as mining. The aim of the study is to gain a deeper understanding of the factors affecting the health and sustainability of young managers in the mining industry. A qualitative case study is conducted based on in-depth interviews with 10 managers aged 35 years or younger at a large international mining company in Northern Europe. A content analysis indicated several straining and facilitating aspects of the work situation in terms of maintaining sustainability and good health. The resulting themes are analyzed and discussed through the lens of the Job-demand-control-support (JDCS) model. Perceived stimulation, growth, and development seems to have a facilitating role in promoting sustainability and health, and is one theme that stood out from complete adaptation to the model. The study contributes with insights into how this model can be applied to a specific professional group (young managers) and in a certain context (mining and similar heavy industry). The findings have practical implications for organizations regarding the ability to ensure good, healthy, attractive, and sustainable working conditions for young managers.
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46. |
- Mörtsell, Edvard, et al.
(author)
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Lens modelling of the strongly lensed Type Ia supernova iPTF16geu
- 2020
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In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 496:3, s. 3270-3280
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Journal article (peer-reviewed)abstract
- In 2016, the first strongly lensed Type Ia supernova (SN Ia), iPTF16geu, at redshift z = 0.409 with four resolved images arranged symmetrically around the lens galaxy at z = 0.2163, was discovered. Here, refined observations of iPTF16geu, including the time delay between images, are used to decrease uncertainties in the lens model, including the the slope of the projected surface density of the lens galaxy, Sigma alpha r(1-eta), and to constrain the universal expansion rate H-0. Imaging with Hubble Space Telescope provides an upper limit on the slope., in slight tension with the steeper density profiles indicated by imaging with Keck after iPTF16geu had faded, potentially due to dust extinction not corrected for in host galaxy imaging. Since smaller. implies larger magnifications, we take advantage of the standard candle nature of SNe Ia constraining the image magnifications, to obtain an independent constraint of the slope. We find that a smooth lens density fails to explain the iPTF16geu fluxes, regardless of the slope, and additional substructure lensing is needed. The total probability for the smooth halo model combined with star microlensing to explain the iPTF16geu image fluxes is maximized at 12 per cent for eta similar to 1.8, in excellent agreement with Keck high-spatial-resolution data, and flatter than an isothermal halo. It also agrees perfectly with independent constraints on the slope from lens velocity dispersion measurements. Combining with the observed time delays between the images, we infer a lower bound on the Hubble constant, H-0 greater than or similar to 40 km s(-1) Mpc(-1), at 68.3 per cent confidence level.
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47. |
- Mörtsell, Edvard, et al.
(author)
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Sensitivity of the Hubble Constant Determination to Cepheid Calibration
- 2022
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In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 933:2
-
Journal article (peer-reviewed)abstract
- Motivated by the large observed diversity in the properties of extragalactic extinction by dust, we reanalyze the Cepheid calibration used to infer the Hubble constant, H0, from Type Ia supernovae, using Cepheid data in 19 Type Ia supernova host galaxies from Riess et al. and anchor data from Riess et al. Unlike the SH0ES team, we do not enforce a fixed universal color–luminosity relation to correct the Cepheid magnitudes. Instead, we focus on a data-driven method, where the optical colors and near-infrared magnitudes of the Cepheids are used to derive individual color–luminosity relations for each Type Ia supernova host and anchor galaxy. We present two different analyses, one based on Wesenheit magnitudes, resulting in H0 = 73.2 ± 1.3 km s−1 Mpc−1, a 4.2σ tension with the value inferred from the cosmic microwave background. In the second approach, we calibrate an individual extinction law for each galaxy, with noninformative priors using color excesses, yielding H0 = 73.9 ± 1.8 km s−1 Mpc−1, in 3.4σ tension with the Planck value. Although the two methods yield similar results, in the latter approach, the Hubble constants inferred from the individual Cepheid absolute distance calibrator galaxies range from H0 = 68.1 ± 3.5 km s−1 Mpc−1 to H0 = 76.7 ± 2.0 km s−1 Mpc−1. Taking the correlated nature of H0 inferred from individual anchors into account, and allowing for individual extinction laws, the Milky Way anchor is in 2.1–3.1 σ tension with the NGC 4258 and Large Magellanic Cloud anchors, depending on prior assumptions regarding the color–luminosity relations and the method used for quantifying the tension.
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48. |
- Mörtsell, Edvard, et al.
(author)
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The Hubble Tension Revisited : Additional Local Distance Ladder Uncertainties
- 2022
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In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 935:1
-
Journal article (peer-reviewed)abstract
- In a recent paper, we investigated possible systematic uncertainties related to the Cepheid color–luminosity calibration method and their influence on the tension between the Hubble constant as inferred from distances to Type Ia supernovae and the cosmic microwave background as measured with the Planck satellite. Here, we study the impact of other sources of uncertainty in the supernova distance ladder, including Cepheid temperature and metallicity variations, supernova magnitudes, and GAIA parallax distances. Using Cepheid data in 19 Type Ia supernova host galaxies from Riess et al., anchor data from Riess et al., and a set of recalibrated Milky Way Cepheid distances, we obtain H0 = 71.9 ± 2.2 km s−1 Mpc−1, 2.0σ from the Planck value. Excluding Cepheids with estimated color excesses Ê(V-I)=0.15 mag to mitigate the impact of the Cepheid color–luminosity calibration, the inferred Hubble constant is H0 = 68.1 ± 2.6 km s−1 Mpc−1, removing the tension with the Planck value.
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49. |
- Nagaraj, Madhu, et al.
(author)
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Chaperones mainly suppress primary nucleation during formation of functional amyloid required for bacterial biofilm formation
- 2022
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In: Chemical Science. - : Royal Society of Chemistry (RSC). - 2041-6520 .- 2041-6539. ; 13:2, s. 536-553
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Journal article (peer-reviewed)abstract
- Unlike misfolding in neurodegenerative diseases, aggregation of functional amyloids involved in bacterial biofilm, e.g. CsgA (E. coli) and FapC (Pseudomonas), is carefully regulated. However, it is unclear whether functional aggregation is inhibited by chaperones targeting pathological misfolding and if so by what mechanism. Here we analyze how four entirely different human chaperones or protein modulators (transthyretin, S100A9, Bri2 BRICHOS and DNAJB6) and bacterial CsgC affect CsgA and FapC fibrillation. CsgA is more susceptible to inhibition than FapC and the chaperones vary considerably in the efficiency of their inhibition. However, mechanistic analysis reveals that all predominantly target primary nucleation rather than elongation or secondary nucleation, while stoichiometric considerations suggest that DNAJB6 and CsgC target nuclei rather than monomers. Inhibition efficiency broadly scales with the chaperones' affinity for monomeric CsgA and FapC. The chaperones tend to target the most aggregation-prone regions of CsgA, but do not display such tendencies towards the more complex FapC sequence. Importantly, the most efficient inhibitors (Bri2 BRICHOS and DNAJB6) significantly reduce bacterial biofilm formation. This commonality of chaperone action may reflect the simplicity of functional amyloid formation, driven largely by primary nucleation, as well as the ability of non-bacterial chaperones to deploy their proteostatic capacities across biological kingdoms.
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50. |
- Pearson Johansson, Joel, 1984-
(author)
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Ground-based and JWST Observations of SN 2022pul. I. Unusual Signatures of Carbon, Oxygen, and Circumstellar Interaction in a Peculiar Type Ia Supernova
- 2024
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In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 960:1
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Journal article (peer-reviewed)abstract
- Nebular-phase observations of peculiar Type Ia supernovae (SNe Ia) provide important constraints on progenitor scenarios and explosion dynamics for both these rare SNe and the more common, cosmologically useful SNe Ia. We present observations from an extensive ground- and space-based follow-up campaign to characterize SN 2022pul, a super-Chandrasekhar mass SN Ia (alternatively "03fg-like" SN), from before peak brightness to well into the nebular phase across optical to mid-infrared (MIR) wavelengths. The early rise of the light curve is atypical, exhibiting two distinct components, consistent with SN Ia ejecta interacting with dense carbon–oxygen (C/O)-rich circumstellar material (CSM). In the optical, SN 2022pul is most similar to SN 2012dn, having a low estimated peak luminosity (MB = −18.9 mag) and high photospheric velocity relative to other 03fg-like SNe. In the nebular phase, SN 2022pul adds to the increasing diversity of the 03fg-like subclass. From 168 to 336 days after peak B-band brightness, SN 2022pul exhibits asymmetric and narrow emission from [O i] λλ6300, 6364 (FWHM ≈ 2000 km s−1), strong, broad emission from [Ca ii] λλ7291, 7323 (FWHM ≈ 7300 km s−1), and a rapid Fe iii to Fe ii ionization change. Finally, we present the first ever optical-to-MIR nebular spectrum of an 03fg-like SN Ia using data from JWST. In the MIR, strong lines of neon and argon, weak emission from stable nickel, and strong thermal dust emission (with T ≈ 500 K), combined with prominent [O i] in the optical, suggest that SN 2022pul was produced by a white dwarf merger within C/O-rich CSM.
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