| 1. |
- ÖZEN, MUSTAFA, 1984, et al.
(författare)
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A Generalized Combiner Synthesis Technique for Class-E Outphasing Transmitters
- 2017
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Ingår i: IEEE Transactions on Circuits and Systems I: Regular Papers. - : Institute of Electrical and Electronics Engineers (IEEE). - 1549-8328 .- 1558-0806. ; 64:5, s. 1126-1139
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, a generic combiner design technique is developed for class-E outphasing transmitters. The design procedure starts with calculation of the combiner network parameters that guarantee high efficiency switch mode operation of the PAs in each branch. Recently developed continuous class-E modes theory is then utilized to create an additional degree of freedom for calculation of the combiner network parameters. This additional degree of freedom along with duty cycle control provides an important possibility for achieving high average efficiency over a large bandwidth. A CMOS-GaN outphasing transmitter prototype is realized for experimental verification. The prototype provides drain efficiencies higher than 60% at 6 dB back-off across 750-1050 MHz band. Further, the peak output power remains nearly flat versus frequency, where the variation across the band is +/- 0.18 dB around 44 dBm.
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| 2. |
- Özkahraman, Özer, 1992-, et al.
(författare)
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Underwater Caging and Capture for Autonomous Underwater Vehicles
- 2020
-
Ingår i: Global Oceans 2020. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we consider the problem of caging and eventual capture of an underwater entity using multiple Autonomous Underwater Vehicles (AUVs) in a 3D water volume We solve this problem both with and without taking bathymetry into account. Our proposed algorithm for range-limited sensing in 3D environments captures a finite-speed entity based on sparse and irregular observations. After an isolated initial sighting of the entity, the uncertainty of its whereabouts grows while deployment of the AUV system is underway. To contain the entity, an initial cage, or barrier of sensing footprints, is created around the initial sighting, using islands and other terrain as part of the cage if available. After the initial cage is established, the system waits for a second sighting, and the possible opportunity to create a smaller, shrinkable cage. This process continues until at some point it is possible to create this smaller cage, resulting in capture, meaning the entity is sensed directly and continuously. We present a set of algorithms for addressing the scenario above, and illustrate their performance on a set of examples. The proposed algorithm is a combination of solutions to the min-cut problem, the set cover problem, the linear bottleneck assignment problem and the Thomson problem.
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| 3. |
- Aad, G., et al.
(författare)
-
- 2012
-
swepub:Mat__t (refereegranskat)
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| 4. |
- Aad, G., et al.
(författare)
-
- 2011
-
Tidskriftsartikel (refereegranskat)
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| 5. |
- Aad, G., et al.
(författare)
-
- 2013
-
Tidskriftsartikel (refereegranskat)
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| 6. |
- Özeren, Hüsamettin Deniz
(författare)
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Prediction of Real Tensile Properties using Extrapolations from Atomistic Simulations: An Assessment on Thermoplastic Starch
- 2021
-
Ingår i: Polymer. - : Elsevier BV. - 0032-3861 .- 1873-2291. ; 228:123919
-
Tidskriftsartikel (refereegranskat)abstract
- Atomistic molecular dynamics (MD) simulations can be used to predict mechanical properties, such as stiffness and strength, for polymers. A concern is unavoidably high strain rates in simulations compared with those in physical experiments. To quantitatively capture the mechanical properties of the ‘real’ material, i.e., to predict absolute values rather than just qualitative trends, extrapolation to realistic strain rates is required. In this study, different strain-rate extrapolation strategies involving time-temperature shifting with the Williams-Landel-Ferry equation (above Tg) and the Eyring equation (below Tg) were evaluated, using thermoplastic starch as an example. MD simulations were first used to compute the stiffness and strength at three (high) strain rates over a wide range of temperatures. The mechanical MD data were then horizontally time-temperature shifted, resulting in master curves with strain-rate (x-axis) versus mechanical properties (y-axis). The precision in the prediction of experimental data was quite good in several cases, but was dependent on the extrapolation method and the specific thermoplastic starch system. A notable finding was that the simulations could be simplified using fewer simulation strain rates and temperatures. The extrapolation techniques used here are expected to be valid for other polymer systems, but this remains to be validated.
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| 7. |
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| 8. |
- Hemlin, S., et al.
(författare)
-
- 2013
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Ingår i: Handbook of Research on Creativity. - : Edward Elgar Publishing Ltd.. - 9780857939814 - 9780857939807 ; , s. 508-521
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 9. |
- Aad, G., et al.
(författare)
-
- 2011
-
swepub:Mat__t (refereegranskat)
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| 10. |
- Özger, Mustafa, et al.
(författare)
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Towards Beyond Visual Line of Sight Piloting of UAVs with Ultra Reliable Low Latency Communication
- 2018
-
Ingår i: 2018 IEEE Global Communications Conference, GLOBECOM 2018 - Proceedings. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781538647271
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we propose a model for beyond visual line of sight (BVLOS) operation for remote piloting of unmanned aerial vehicles (UAVs), which utilizes different technologies such as mobile edge computing and augmented reality. Ultra reliable low latency communication (URLLC) is a key service of 5G that enables safe BVLOS operation. Since message size of piloting signal is finite and communication channel is altitude dependent, we study reliability and latency under finite blocklength regime for different altitudes. In our numerical study, we find that for message sizes 30 and 50 bits, coded packet size, i.e., blocklength, should be in the range of 200 and 300 bits to enable BVLOS operation. We also found that minimum distance between UAVs to avoid any crash should be around 0.2 m for 15 m/s UAV speed and different altitudes ranging from 1.5 m to 120 m. According to our study, BVLOS operation of UAVs can be realized by URLLC by providing error probability in the vicinity of 10(-3), and latency on the order of milliseconds for downlink communication with blocklength of tens to hundred bits.
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| 11. |
- Lind, Johan, et al.
(författare)
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Students' knowledge of emerging technology and sustainability through a design activity in technology education
- 2022
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Ingår i: International journal of technology and design education. - : Springer. - 0957-7572 .- 1573-1804. ; 32, s. 243-266
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study is to explore whether, and if so how, a design activity could encourage students to express and develop knowledge on emerging technology in relation to issues about sustainability. Several researchers have asserted that, in today's technologically dependent society, it is important to be able to control technology and make informed decisions connected to technology. Design activities could make a significant contribution to technology education while students are developing their knowledge about technology. Thus, the present study aims to analyze students' verbal interactions as they work in a design project, which includes designing a model of a house, regarding their ability to develop technological literacy with the support of a physical model. The study is based on several small-group interactions that were recorded, transcribed, analyzed, and discussed. This research project was conducted as an observation of technology education in a Swedish compulsory school. The students (aged 13-14) negotiated and shared knowledge about technology as they interacted with their fellow students. The results indicate that, in a relatively large number of situations, the students expressed knowledge about emerging technology and adopted a sustainability perspective while working in a design activity, and thereby, successively developed technological literacy. This meant that the students were able to integrate knowledge on emerging technology like graphene, nanotechnology, and algae batteries in their models. Furthermore, the results indicate that, during technical development work, students were able to develop reasoning, communication, and collaboration skills.
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| 12. |
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| 13. |
- Aamodt, K., et al.
(författare)
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The ALICE experiment at the CERN LHC
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3:S08002
-
Forskningsöversikt (refereegranskat)abstract
- ALICE (A Large Ion Collider Experiment) is a general-purpose, heavy-ion detector at the CERN LHC which focuses on QCD, the strong-interaction sector of the Standard Model. It is designed to address the physics of strongly interacting matter and the quark-gluon plasma at extreme values of energy density and temperature in nucleus-nucleus collisions. Besides running with Pb ions, the physics programme includes collisions with lighter ions, lower energy running and dedicated proton-nucleus runs. ALICE will also take data with proton beams at the top LHC energy to collect reference data for the heavy-ion programme and to address several QCD topics for which ALICE is complementary to the other LHC detectors. The ALICE detector has been built by a collaboration including currently over 1000 physicists and engineers from 105 Institutes in 30 countries, Its overall dimensions are 16 x 16 x 26 m(3) with a total weight of approximately 10 000 t. The experiment consists of 18 different detector systems each with its own specific technology choice and design constraints, driven both by the physics requirements and the experimental conditions expected at LHC. The most stringent design constraint is to cope with the extreme particle multiplicity anticipated in central Pb-Pb collisions. The different subsystems were optimized to provide high-momentum resolution as well as excellent Particle Identification (PID) over a broad range in momentum, up to the highest multiplicities predicted for LHC. This will allow for comprehensive studies of hadrons, electrons, muons, and photons produced in the collision of heavy nuclei. Most detector systems are scheduled to be installed and ready for data taking by mid-2008 when the LHC is scheduled to start operation, with the exception of parts of the Photon Spectrometer (PHOS), Transition Radiation Detector (TRD) and Electro Magnetic Calorimeter (EMCal). These detectors will be completed for the high-luminosity ion run expected in 2010. This paper describes in detail the detector components as installed for the first data taking in the summer of 2008.
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| 14. |
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| 15. |
- Rodríguez-Gijón, Alejandro, 1996-, et al.
(författare)
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Shotgun metagenomes from productive lakes in an urban region of Sweden
- 2023
-
Ingår i: Scientific Data. - 2052-4463. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- Urban lakes provide multiple benefits to society while influencing life quality. Moreover, lakes and their microbiomes are sentinels of anthropogenic impact and can be used for natural resource management and planning. Here, we release original metagenomic data from several well-characterized and anthropogenically impacted eutrophic lakes in the vicinity of Stockholm (Sweden). Our goal was to collect representative microbial community samples and use shotgun sequencing to provide a broad view on microbial diversity of productive urban lakes. Our dataset has an emphasis on Lake Mälaren as a major drinking water reservoir under anthropogenic impact. This dataset includes short-read sequence data and metagenome assemblies from each of 17 samples collected from eutrophic lakes near the greater Stockholm area. We used genome-resolved metagenomics and obtained 2378 metagenome assembled genomes that de-replicated into 514 species representative genomes. This dataset adds new datapoints to previously sequenced lakes and it includes the first sequenced set of metagenomes from Lake Mälaren. Our dataset serves as a baseline for future monitoring of drinking water reservoirs and urban lakes.
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| 16. |
- Zhiyong, Liu, et al.
(författare)
-
Anionic nanoplastic contaminants promote Parkinson’s disease–associated α-synuclein aggregation
- 2023
-
Ingår i: Science Advances. - 2375-2548. ; 9:46
-
Tidskriftsartikel (refereegranskat)abstract
- Recent studies have identified increasing levels of nanoplastic pollution in the environment. Here, we find that anionic nanoplastic contaminants potently precipitate the formation and propagation of α-synuclein protein fibrils through a high-affinity interaction with the amphipathic and non-amyloid component (NAC) domains in α-synuclein. Nanoplastics can internalize in neurons through clathrin-dependent endocytosis, causing a mild lysosomal impairment that slows the degradation of aggregated α-synuclein. In mice, nanoplastics combine with α-synuclein fibrils to exacerbate the spread of α-synuclein pathology across interconnected vulnerable brain regions, including the strong induction of α-synuclein inclusions in dopaminergic neurons in the substantia nigra. These results highlight a potential link for further exploration between nanoplastic pollution and α-synuclein aggregation associated with Parkinson’s disease and related dementias.
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| 17. |
- Bouvier, Laura, et al.
(författare)
-
Evidence for extremely rapid magma ocean crystallization and crust formation on Mars
- 2018
-
Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 558, s. 586-589
-
Tidskriftsartikel (refereegranskat)abstract
- The formation of a primordial crust is a critical step in the evolution of terrestrial planets but the timing of this process is poorly understood. The mineral zircon is a powerful tool for constraining crust formation because it can be accurately dated with the uranium-to-lead (U–Pb) isotopic decay system and is resistant to subsequent alteration. Moreover, given the high concentration of hafnium in zircon, the lutetium-to-hafnium (176Lu–176Hf) isotopic decay system can be used to determine the nature and formation timescale of its source reservoir (1,2,3) Ancient igneous zircons with crystallization ages of around 4,430 million years (Myr) have been reported in Martian meteorites that are believed to represent regolith breccias from the southern highlands of Mars (4,5) These zircons are present in evolved lithologies interpreted to reflect re-melted primary Martian crust4, thereby potentially providing insight into early crustal evolution on Mars. Here, we report concomitant high-precision U–Pb ages and Hf-isotope compositions of ancient zircons from the NWA 7034 Martian regolith breccia. Seven zircons with mostly concordant U–Pb ages define 207Pb/206Pb dates ranging from 4,476.3 ± 0.9 Myr ago to 4,429.7 ± 1.0 Myr ago, including the oldest directly dated material from Mars. All zircons record unradiogenic initial Hf-isotope compositions inherited from an enriched, andesitic-like crust extracted from a primitive mantle no later than 4,547 Myr ago. Thus, a primordial crust existed on Mars by this time and survived for around 100 Myr before it was reworked, possibly by impacts (4,5) to produce magmas from which the zircons crystallized. Given that formation of a stable primordial crust is the end product of planetary differentiation, our data require that the accretion, core formation and magma ocean crystallization on Mars were completed less than 20 Myr after the formation of the Solar System. These timescales support models that suggest extremely rapid magma ocean crystallization leading to a gravitationally unstable stratified mantle, which subsequently overturns, resulting in decompression melting of rising cumulates and production of a primordial basaltic to andesitic crust (6,7).
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| 18. |
- Tabariès, Sébastien, et al.
(författare)
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Afadin cooperates with Claudin-2 to promote breast cancer metastasis
- 2019
-
Ingår i: Genes & Development. - : Cold Spring Harbor Laboratory. - 1549-5477 .- 0890-9369. ; 33:3-4, s. 180-193
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Tidskriftsartikel (refereegranskat)abstract
- Claudin-2 promotes breast cancer liver metastasis by enabling seeding and early cancer cell survival. We now demonstrate that the PDZ-binding motif of Claudin-2 is necessary for anchorage-independent growth of cancer cells and is required for liver metastasis. Several PDZ domain-containing proteins were identified that interact with the PDZ-binding motif of Claudin-2 in liver metastatic breast cancer cells, including Afadin, Arhgap21, Pdlim2, Pdlim7, Rims2, Scrib, and ZO-1. We specifically examined the role of Afadin as a potential Claudin-2-interacting partner that promotes breast cancer liver metastasis. Afadin associates with Claudin-2, an interaction that requires the PDZ-binding motif of Claudin-2. Loss of Afadin also impairs the ability of breast cancer cells to form colonies in soft agar and metastasize to the lungs or liver. Immunohistochemical analysis of Claudin-2 and/or Afadin expression in 206 metastatic breast cancer tumors revealed that high levels of both Claudin-2 and Afadin in primary tumors were associated with poor disease-specific survival, relapse-free survival, lung-specific relapse, and liver-specific relapse. Our findings indicate that signaling downstream from a Claudin-2/Afadin complex enables the efficient formation of breast cancer metastases. Moreover, combining Claudin-2 and Afadin as prognostic markers better predicts the potential of breast cancer to metastasize to soft tissues.
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| 19. |
- Abat, E., et al.
(författare)
-
A layer correlation technique for pion energy calibration at the 2004 ATLAS Combined Beam Test
- 2011
-
Ingår i: Journal of Instrumentation. - : Institute of Physics (IOP). - 1748-0221. ; 6
-
Tidskriftsartikel (refereegranskat)abstract
- A new method for calibrating the hadron response of a segmented calorimeter is developed and successfully applied to beam test data. It is based on a principal component analysis of energy deposits in the calorimeter layers, exploiting longitudinal shower development information to improve the measured energy resolution. Corrections for invisible hadronic energy and energy lost in dead material in front of and between the calorimeters of the ATLAS experiment were calculated with simulated Geant4 Monte Carlo events and used to reconstruct the energy of pions impinging on the calorimeters during the 2004 Barrel Combined Beam Test at the CERN H8 area. For pion beams with energies between 20 GeV and 180 GeV, the particle energy is reconstructed within 3% and the energy resolution is improved by between 11% and 25% compared to the resolution at the electromagnetic scale.
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| 20. |
- Abat, E., et al.
(författare)
-
Combined performance studies for electrons at the 2004 ATLAS combined test-beam
- 2010
-
Ingår i: Journal of Instrumentation. - : Institute of Physics (IOP). - 1748-0221. ; 5, s. P11006-
-
Tidskriftsartikel (refereegranskat)abstract
- In 2004 at the ATLAS (A Toroidal LHC ApparatuS) combined test beam, one slice of the ATLAS barrel detector (including an Inner Detector set-up and the Liquid Argon calorimeter) was exposed to particles from the H8 SPS beam line at CERN. It was the first occasion to test the combined electron performance of ATLAS. This paper presents results obtained for the momentum measurement p with the Inner Detector and for the performance of the electron measurement with the LAr calorimeter (energy E linearity and resolution) in the presence of a magnetic field in the Inner Detector for momenta ranging from 20 GeV/c to 100 GeV/c. Furthermore the particle identification capabilities of the Transition Radiation Tracker, Bremsstrahlungs-recovery algorithms relying on the LAr calorimeter and results obtained for the E/p ratio and a way how to extract scale parameters will be discussed.
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| 21. |
- Abat, E., et al.
(författare)
-
Photon reconstruction in the ATLAS Inner Detector and Liquid Argon Barrel Calorimeter at the 2004 Combined Test Beam
- 2011
-
Ingår i: Journal of Instrumentation. - 1748-0221. ; 6
-
Tidskriftsartikel (refereegranskat)abstract
- The reconstruction of photons in the ATLAS detector is studied with data taken during the 2004 Combined Test Beam, where a full slice of the ATLAS detector was exposed to beams of particles of known energy at the CERN SPS. The results presented show significant differences in the longitudinal development of the electromagnetic shower between converted and unconverted photons as well as in the total measured energy. The potential to use the reconstructed converted photons as a means to precisely map the material of the tracker in front of the electromagnetic calorimeter is also considered. All results obtained are compared with a detailed Monte-Carlo simulation of the test-beam setup which is based on the same simulation and reconstruction tools as those used for the ATLAS detector itself.
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| 22. |
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| 23. |
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| 24. |
- Bensow, Rickard, 1972, et al.
(författare)
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Using a PANS Simulation Approach for the Transient Flow around the Japan Bulk Carrier
- 2019
-
Ingår i: Journal of Ship Research. - 1542-0604 .- 0022-4502. ; 63:2, s. 123-129
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, a partially averaged Navier-Stokes 9PANS) modeling approach developed based on the k-omega turbulence model has been applied to the flow around the Japan Bulk Carrier. Three different meshes have been used for a fixed physical resolution for the PANS modeling. The results are encouraging, with small-scale flow dynamics being allowed to develop on reasonably small mesh sizes, but more studies are required before reliable predictive simulations can be performed.
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| 25. |
- Abat, E., et al.
(författare)
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Study of the response of the ATLAS central calorimeter to pions of energies from 3 to 9 GeV
- 2009
-
Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002 .- 1872-9576. ; 607:2, s. 372-386
-
Tidskriftsartikel (refereegranskat)abstract
- A fully instrumented slice of the ATLAS central detector was exposed to test beams from the SPS (Super Proton Synchrotron) at CERN in 2004. in this paper, the response of the central calorimeters to pions with energies in the range between 3 and 9 GeV is presented. The linearity and the resolution of the combined calorimetry (electromagnetic and hadronic calorimeters) was measured and compared to the prediction of a detector simulation program using the toolkit Geant 4. (C) 2009 Elsevier B.V. All rights reserved.
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| 26. |
- Aad, G., et al.
(författare)
-
- 2014
-
Ingår i: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; :11
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Tidskriftsartikel (refereegranskat)
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| 27. |
- Abata, E., et al.
(författare)
-
Study of energy response and resolution of the ATLAS barrel calorimeter to hadrons of energies from 20 to 350 GeV
- 2010
-
Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576 .- 0167-5087. ; 621:1-3, s. 134-150
-
Tidskriftsartikel (refereegranskat)abstract
- A fully instrumented slice of the ATLAS detector was exposed to test beams from the SPS (Super Proton Synchrotron) at CERN in 2004. In this paper, the results of the measurements of the response of the barrel calorimeter to hadrons with energies in the range 20-350 GeV and beam impact points and angles corresponding to pseudo-rapidity values in the range 0.2-0.65 are reported. The results are compared to the predictions of a simulation program using the Geant 4 toolkit. (C) 2010 Published by Elsevier B.V.
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| 28. |
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| 29. |
- Theorell, Töres, et al.
(författare)
-
Saliva testosterone and heart rate variability in the professional symphony orchestra after "public faintings" of an orchestra member
- 2007
-
Ingår i: Psychoneuroendocrinology. - : Elsevier BV. - 0306-4530 .- 1873-3360. ; 32:6, s. 660-668
-
Tidskriftsartikel (refereegranskat)abstract
- Musicians are sensitive to changes in their work environment. A 2-year longitudinal study with repeated observations was performed in two professional symphony orchestras. A representative sample from each one of them was selected, 15 and 16 members respectively. In one of them a wind player fainted twice in front of the audience shortly preceding and coinciding with the start of the study. Changes in two indicators that reflect regenerative/anabolic and parasympathetic tone, saliva testosterone concentration (STC) and very low-frequency power (VLFP) in heart rate variability were followed in relation to this dramatic change. Saliva samples and 24-h ECG heart rate variability recordings were collected on five occasions every 6 months during a 2-year period. No changes were seen in the control orchestra whereas the levels showed a pronounced rise in the intervention orchestra during the first part of the study, starting from low levels. VLFP showed a similar pattern, with initially low and then rising level in the intervention orchestra and higher stable level in the other group. In the total study group, a rise in STC over the whole observation period was significantly correlated with increase in VLFP and also significantly correlated with a decrease in low/high-frequency power ratio in heart rate variability. The changes observed in the anabolic/regenerative STC and the parasympathetically influenced VLFP may reflect changes in the work environment associated with the faintings.
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| 30. |
- Di Bari, Chiara, et al.
(författare)
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Halides inhibition of multicopper oxidases studied by FTIR spectroelectrochemistry using azide as an active infrared probe
- 2017
-
Ingår i: Journal of Biological Inorganic Chemistry. - : Springer. - 0949-8257 .- 1432-1327. ; 22:8, s. 1179-1186
-
Tidskriftsartikel (refereegranskat)abstract
- An IR spectroelectrochem. study of Trametes hirsuta laccase and Magnaporthe oryzae bilirubin oxidase has been performed using azide, an inhibitor of multicopper oxidases, as an active IR probe incorporated into the T2/T3 copper cluster of the enzymes. The redox potential-controlled measurements indicate that N3- stretching IR bands of azide ion bound to the T2/T3 cluster are only detected for the oxidized enzymes, confirming that azide only binds to Cu2+. Moreover, the process of binding/dissocn. of azide ion is shown to be reversible. The interaction of halide anions, which also inhibit multicopper oxidases, with the active site of the enzymes was studied by measuring the changes in the azide FTIR bands. Enzymes inhibited by azide respond differently upon addn. of fluoride or chloride ions to the sample soln. inhibited by azide. Fluoride ions compete with azide for binding at one of the T2/T3 Cu ions, whereas competition from chloride ions is much less evident.
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| 31. |
- de Anca Prado, Violeta, 1996-, et al.
(författare)
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Discovering the world of fossil fungi
- 2020
-
Ingår i: Deposits Magazine. - Southwold, UK : UKGE Limited. - 1744-9588. ; 2020, s. 1-7
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- When people think of fossils, they usually picture slabs of rock bristling with bones, or the shells of ammonites or trilobites. Most do not even consider that delicate organisms, such as fungi or bacteria, can even fossilize – they seem too fragile to be preserved as they lack a hard skeleton. In many cases this is true. Microscopic organisms that lack hard parts have fewer chances of being fossilised but, despite the odds, delicate fungi have a fossil record that is more extensive than generally thought.
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| 32. |
- Forooraghi, Melina, 1989, et al.
(författare)
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A healthy office and healthy employees: a longitudinal case study with a salutogenic perspective in the context of the physical office environment
- 2022
-
Ingår i: Building Research and Information. - : Informa UK Limited. - 1466-4321 .- 0961-3218. ; 50:1-2, s. 134-151
-
Tidskriftsartikel (refereegranskat)abstract
- This two-wave study (time lag of six months and two years post-relocation) investigated ways in which employees’ perceptions of the office environment relate to their perceived health in the long term, drawing on the salutogenic approach to health and the sense of coherence theory (comprehensibility, manageability, and meaningfulness). A mixed-method approach was adopted. The data collection involved semi-structured interviews with employees, plus structured observations. The findings indicate that employees found the office environment less comprehensible and meaningful in Wave 2, while (somewhat) equally manageable. Comprehensibility was influenced by a lack of clear behavioural rules; manageability was influenced by a lack of control over the environment; and meaningfulness was influenced by social environment and lack of personalization. The contextual aspects of the office, including tasks, flexible working culture and the change processes were critical to these findings. This study has demonstrated that negative influences caused by poor design choices do not resolve themselves over time. When there is limited support for one component of sense of coherence, the initial observed benefits wear off and negative influences may spill over into other components. Therefore, office design should be approached with balanced attention to comprehensibility, manageability, and meaningfulness.
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| 33. |
- Amatayakul, Wathanyu, 1975
(författare)
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At the crossroads of bioenergy and agriculture in developing countries : Challenges and prospects for fossil fuels replacement and CO2 abatement in the case of Thailand
- 2007
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Studies estimate that the potential contribution of biomass to the global primary energy supply from cultivation of crops for energy is substantial in the long term, from about 50 to 240 EJ/year in 2050. Most of this biomass is projected to come from cultivation in developing countries. Yet, most studies estimate the theoretical potential from a top-down perspective and there is a lack of detailed analyses and understanding of the present development of various bioenergy plantations in developing countries. Major challenges in implementing bioenergy plantations involve other competitive sources of energy, competitive uses of biomass and land, and impact on food crops production and environmental impacts of production. A better understanding of these challenges would help realize the “practical” potential of biomass from plantations for energy as well as help in designing policies to assure that the plantations will lead to global and national benefits without compromising local livelihood and environment. This licentiate thesis investigates these challenges and the prospects for substituting biomass from plantations for fossil fuels and CO2 abatement at the local and country level in the case of Thailand.In the first paper, we analyze 1) the levelized cost of production of eucalyptus wood, 2) to what extent the economics of the production improve if the biospheric carbon stock changes are credited, and 3) the abatement cost of substituting eucalyptus wood for fossil fuels for electricity generation. The levelized cost of wood is estimated at 1.2-1.7 USD/GJ. We find that, given a carbon permit price of 10 USD/ton-C, carbon crediting could reduce the establishment cost of the plantation by 100 USD/hectare (20-50%) or reduce the levelized cost of wood by 0.2 USD/GJ (10-20%). The cost of substituting a wood-fired plant for a coal-fired and a gas-fired power plant is estimated at 107 and 196 USD/ton-C. The prospects of eucalyptus plantations for electricity generation and CO2 abatement also depends on several factors that affect farmers’ decisions to plant eucalyptus.In the second paper, we seek to answer the following questions: 1) what are the characteristics of farmers who commercially plant woody energy crops? 2) what determines their planting decisions? and 3) on which types of land are the crops planted? We survey the characteristics of the commercial growers and non-growers of eucalyptus trees by interviews and apply econometric models to analyze the determining factors of, first, the farmers’ decision to plant eucalyptus and, second, how large an area to plant with eucalyptus. We find that eucalyptus growers have on average three times larger farm size and a higher annual family income. The most important factor that increases the likelihood of planting eucalyptus is having a large farm. We show that who cultivates a given parcel of land—several small-scale subsistence farmers or a single wealthier farmer—significantly determines the amount of land used for wood cultivation. In addition, eucalyptus and cassava price is the most important factor determining the fraction of the total land used for eucalyptus. Land quality does not significantly affect the planting decisions, and eucalyptus is planted both on lands unsuitable and suitable for food crops (mainly cassava).In the third paper, we analyze the trade-offs in achieving the government’s national ethanol program target of replacing all conventional gasoline with E10 gasohol (gasoline containing ethanol at 10% by volume), by 2012. Achieving the target leads to the following impacts over the period 2005-2012: 1) a displacement of the areas of maize and rice up to 0.2 million hectare; 2) a net trade change ranging from negative 110 MUSD to positive 190 MUSD per year; 3) an increase in the self-sufficiency rate of gasoline from 10 to 20% and a decrease in the self-sufficiency rate of molasses from 165 to 100%, and of cassava and maize from 420 to 330% and from 120 to 95% at the lowest, respectively; and 4) a total GHG emissions reduction of 4.0 million tons CO2 equivalent (CO2e). The annual average cost of substituting gasohol for gasoline is estimated at 25-195 USD/ton-CO2e and is high compared with the price of project-based certified emissions reductions traded during 2006 but low compared with estimates of the cost of substituting biofuels for fossil fuels in Europe. The cost of tax revenues foregone in implementing the program is estimated at 2-4 times higher than the gasoline substitution cost. Compared to proposed projects on biofuels for blending with fossil fuels under the clean development mechanism (CDM), the ethanol program could avoid the issue of additionality and double counting and also has some other advantages.
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| 34. |
- Ye, Y., et al.
(författare)
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High Capacity Transport associated with Pre- and Post- Haulage in Intermodal Road-Rail Transport
- 2014
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Ingår i: Journal of Transportation Technologies. - : Scientific Research Publishing, Inc.. - 2160-0473 .- 2160-0481. ; 4:3, s. 289-301
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Tidskriftsartikel (refereegranskat)abstract
- This paper develops a model for analysing the potential of longer and heavier vehicles (LHVs) related to pre- and post-haulage in the intermodal rail-road transport chain (IRT). The paper considers the combined economic and emission costs among three different transport networks including intermodal rail-road transport with current Swedish regulatory framework for trucks, intermodal rail-road transport with LHVs, and direct-road transport. The contribution of the LHVs to the cost efficiency of the intermodal network is indicated by the traffic volume break-even among the three transport networks. The objective is to analyse the potential of high-capacity transport associated with pre- and post- haulage for enhancing the competitiveness of intermodal transport from a full-costs perspective. The model developed is applied to a Swedish context and case study. Research findings reveal that the break-even of the IRT compared to direct road transport could be significantly lowered, which suggests the LHVs contribute to exploring the market of IRT over smaller flow.
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| 35. |
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| 36. |
- Pedersen, Marie, et al.
(författare)
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Meniscus or Cartilage Injury at the Time of Anterior Cruciate Ligament Tear Is Associated With Worse Prognosis for Patient-Reported Outcome 2 to 10 Years After Anterior Cruciate Ligament Injury : A Systematic Review
- 2020
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Ingår i: Journal of Orthopaedic and Sports Physical Therapy. - : Journal of Orthopaedic & Sports Physical Therapy (JOSPT). - 0190-6011 .- 1938-1344. ; 50:9, s. 490-502
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Forskningsöversikt (refereegranskat)abstract
- OBJECTIVES: (1) To assess prognostic factors for patient-reported outcome measures (PROMs) and physical activity 2 to 10 years after anterior cruciate ligament reconstruction (ACLR) or anterior cruciate ligament (ACL) injury, and (2) to assess differences in prognostic factors between patients treated with ACLR and with rehabilitation alone.DESIGN: Prognosis systematic review.LITERATURE SEARCH: Systematic searches were performed in PubMed, Web of Science, and SPORTDiscus.STUDY SELECTION CRITERIA: We selected prospective cohort studies and randomized clinical trials that included adults or adolescents undergoing either ACLR or rehabilitation alone after ACL rupture. Studies had to assess the statistical association between potential prognostic factors (factors related to patient characteristics, injury, or knee symptoms/function measured at baseline or within 1 year) and outcomes (PROMs and physical activity).DATA SYNTHESIS: Our search yielded 997 references. Twenty studies met the inclusion criteria. Seven studies with low or moderate risk of bias remained for data synthesis.RESULTS: Moderate-certainty evidence indicated that concomitant meniscus and cartilage injuries were prognostic factors for worse PROMs 2 to 10 years after ACLR. Very low-certainty evidence suggested that body mass index, smoking, and baseline PROMs were prognostic factors for worse outcome. Very low-certainty evidence suggested that female sex and a worse baseline Marx Activity Rating Scale score were prognostic factors for a worse Marx Activity Rating Scale score 2 to 10 years after ACLR. There was a lack of studies on prognostic factors after rehabilitation alone.CONCLUSION: Concomitant meniscus and cartilage injuries were prognostic factors for worse long-term PROMs after ACLR. The certainty was very low for other prognostic factors. J Orthop Sports Phys Ther 2020;50(9):490-502. Epub 1 Aug 2020. doi:10.2519/jospt.2020.9451.
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| 37. |
- Winikoff, Michael, et al.
(författare)
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Evaluating a Mechanism for Explaining BDI Agent Behaviour
- 2023
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Ingår i: Proceedings of the 5th International Workshop on EXTRAAMAS 2023. - Heidelberg : Springer. - 9783031408779 ; , s. 18-37
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Konferensbidrag (refereegranskat)abstract
- Explainability of autonomous systems is important to supporting the development of appropriate levels of trust in the system, as well as supporting system predictability. Previous work has proposed an explanation mechanism for Belief-Desire-Intention (BDI) agents that uses folk psychological concepts, specifically beliefs, desires, and valuings. In this paper we evaluate this mechanism by conducting a survey. We consider a number of explanations, and assess to what extent they are considered believable, acceptable, and comprehensible, and which explanations are preferred. We also consider the relationship between trust in the specific autonomous system, and general trust in technology. We find that explanations that include valuings are particularly likely to be preferred by the study participants, whereas those explanations that include links are least likely to be preferred. We also found evidence that single-factor explanations, as used in some previous work, are too short. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
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| 38. |
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| 39. |
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| 40. |
- Rystedt, Hans, 1951, et al.
(författare)
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Developing nursing expertise in simulation-based learning environments
- 2003
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Ingår i: Collaboration and Learning in Virtual Environments. - 9513914208 ; , s. 87-108
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Konferensbidrag (refereegranskat)abstract
- The work of nurse anaesthetists is carried out in a highly technological environment, where patient care is provided in close collaboration with other members of hospital staff. The expertise of these nurses and how this is developed is of vital importance. Furthermore, the use of computerised pedagogical tools to support learning within an educational setting is of special interest. The main aim of this paper is to investigate how the use of one of these tools, a simulation based learning environment, can contribute to learning in the domain of anaesthesia care. The study is carried out within the framework of socio-cultural theory. From this perspective, learning is viewed as being situated in communities of practice, where interaction between individuals, and between artefacts and individuals, is considered as central in the learning process. Here, we will present results from a study of how trainee nurse anaesthetists use computer simulations and discuss issues concerning their learning processes. The planning, implementation and debriefing phases of one training session are scrutinised with respect to the framing of problems and implications for learning. The results support the assumption that work in computer based learning environments can influence assessment procedures and decision making skills in significant ways, and that computer-based learning environments provide productive means for goal directed collaborative learning activities.
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| 41. |
- Zhang, Wenxin, et al.
(författare)
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Tundra shrubification and tree-line advance amplify arctic climate warming : results from an individual-based dynamic vegetation model
- 2013
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Ingår i: Environmental Research Letters. - : IOP Publishing. - 1748-9326. ; 8:3
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Tidskriftsartikel (refereegranskat)abstract
- One major challenge to the improvement of regional climate scenarios for the northern high latitudes is to understand land surface feedbacks associated with vegetation shifts and ecosystem biogeochemical cycling. We employed a customized, Arctic version of the individual-based dynamic vegetation model LPJ-GUESS to simulate the dynamics of upland and wetland ecosystems under a regional climate model-downscaled future climate projection for the Arctic and Subarctic. The simulated vegetation distribution (1961-1990) agreed well with a composite map of actual arctic vegetation. In the future (2051-2080), a poleward advance of the forest-tundra boundary, an expansion of tall shrub tundra, and a dominance shift from deciduous to evergreen boreal conifer forest over northern Eurasia were simulated. Ecosystems continued to sink carbon for the next few decades, although the size of these sinks diminished by the late 21st century. Hot spots of increased CH4 emission were identified in the peatlands near Hudson Bay and western Siberia. In terms of their net impact on regional climate forcing, positive feedbacks associated with the negative effects of tree-line, shrub cover and forest phenology changes on snow-season albedo, as well as the larger sources of CH4, may potentially dominate over negative feedbacks due to increased carbon sequestration and increased latent heat flux.
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| 42. |
- Hagell, Peter, et al.
(författare)
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Measuring fatigue in Parkinsons disease: A psychometric study of two brief generic fatigue questionnaires
- 2006
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Ingår i: Journal of Pain and Symptom Management. - : Elsevier BV. - 0885-3924 .- 1873-6513. ; 32:5, s. 420-432
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Tidskriftsartikel (refereegranskat)abstract
- This study evaluated and compared the measurement properties of the 13-item Functional Assessment of Chronic Illness Therapy-Fatigue Scale (FACIT-F) and the 9-item Fatigue Severity Scale (FSS) in 118 consecutive Parkinsons disease (PD) patients, using traditional and Rasch measurement methodologies. Both questionnaires exhibited excellent data quality and reliability (coefficient alpha greater than= 0.9), and acceptable rating scale functionality, and both discriminated between fatigued and nonfatigued patients. factor and Rasch analyses provided general support for unidimensionality of both FACIT-F and FSS, although they do not appear to measure identical aspects of fatigue. No signs of differential item functioning (DIF) were found for the FACIT-F, whereas potential age DIF, was detected for two FSS items. These results support the measurement validity of both questionnaires in PD, although the FACIT-F displayed better measurement precision and modest psychometric advantages over the FSS. Availability of psychometrically sound fatigue measures that are applicable across disorders provides a sound basis for advancing the understanding of this common and distressing complaint.
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| 43. |
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| 44. |
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| 45. |
- Wang, Yi-ting, et al.
(författare)
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Women's rights in democratic transitions : A global sequence analysis, 1900-2012
- 2017
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Ingår i: European Journal of Political Research. - : WILEY. - 0304-4130 .- 1475-6765. ; 56:4, s. 735-756
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Tidskriftsartikel (refereegranskat)abstract
- What determines countries' successful transition to democracy? This article explores the impact of granting civil rights in authoritarian regimes and especially the gendered aspect of this process. It argues that both men's and women's liberal rights are essential conditions for democratisation to take place: providing both women and men rights reduces an inequality that affects half of the population, thus increasing the costs of repression and enabling the formation of women's organising - historically important to spark protests in initial phases of democratisation. This argument is tested empirically using data that cover 173 countries over the years 1900-2012 and contain more nuanced measures than commonly used. Through novel sequence analysis methods, the results suggest that in order to gain electoral democracy a country first needs to furnish civil liberties to both women and men.
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| 46. |
- Beorchia, Valentina, et al.
(författare)
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Eigenschemes of Ternary Tensors
- 2021
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Ingår i: SIAM JOURNAL ON APPLIED ALGEBRA AND GEOMETRY. - : Society for Industrial & Applied Mathematics (SIAM). - 2470-6566. ; 5:4, s. 620-650
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Tidskriftsartikel (refereegranskat)abstract
- We study projective schemes arising from eigenvectors of tensors, called eigenschemes. After some general results, we give a birational description of the variety parametrizing eigenschemes of general ternary symmetric tensors, and we compute its dimension. Moreover, we characterize the locus of triples of homogeneous polynomials defining the eigenscheme of a ternary symmetric tensor. Our results allow us to implement algorithms to check whether a given set of points is the eigenscheme of a symmetric tensor and to reconstruct the tensor. Finally, we give a geometric characterization of all reduced zero-dimensional eigenschemes. The techniques we use rely on both classical and modern complex projective algebraic geometry.
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| 47. |
- Düppe, Henrik
(författare)
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Bone mass in young adults - determinants and fracture prediction.
- 1997
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Bone mass in adolescents and young adults was studied with regard to its age-related change and its determinants. Methodological aspects of bone mass measurements and their ability to predict future fractures were investigated. Bone mineral content (BMC) and bone mineral density (BMD) were assessed by the Single Photon Absorptiometry (SPA) and Dual Energy X-ray Absorptiometry (DXA) techniques. We demonstrate that results, when normative bone mass data are being collected, may depend on whether the study is population-based with randomly selected probands or selected by other means. Participation rate may also influence the outcome. In the same study population, higher BMD levels at several skeletal sites were found by increasing the participation-rate from 61.9 to 83.6%. A limited but significant reduction of forearm cortical BMD in women (<70 years) over the past two decades was found by comparing two samples of healthy women (n=271 and n=155). We conlude that this may be due to life-style changes. In a cross-sectional study of 332 subjects (175 men), age 15-42 years, peak bone mass occurred for both sexes at approximately age 20 in the hip and age 30 in the forearm, lumbar spine and total body. The drop in BMD following peak bone mass was most pronounced in the hip. In this study, 112 subjects (57 men) were studied longitudinally (mean 3.4 years). A high degree of conformity between cross-sectional and longitudinal bone mass data in the description of the age-related change in BMD was found. In a population-based study of 39 girls and 48 boys, childhood weight was found to be predictive of adolescent total body BMC but not total body BMD. This suggests that growth determines the size of the skeleton, whereas the density within that bone envelope is to a greater extent governed by other factors such as physical activity. Familial resemblance in BMD was studied in 40 biological daughter-mother-grandmother triads and 20 biological daughter-mother pairs. A significant correlation was found between age- and maturity-adjusted BMD Z-scores at all sites in the D-M relationship (r=0.25 - 0.39), only in the head for the M-G relationship (r=0.40) and not at all in the D-G relationship. This implies that environmental factors may modify the genetic impact on familial resemblance. In a study of active (n=96) and former (n=25) female fotball players we found higher BMD values in active players when compared with matched controls at several skeletal sites, most pronounced in the hip. The BMD advantage over controls was preserved in former players that had ended their active careers on an average 9.7 years prior to the study. A single bone density measurement of the forearm in a study including 410 women, was found to be predictive of a future fracture on a 25 year perspective. The relative risk (RR) of a fracture with a 1 SD decrease in BMD was 1.33 for all fragility fractures and 1.66 for a hip fracture.
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| 48. |
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| 49. |
- Sartipy, Ulrik, et al.
(författare)
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Predicting survival in heart failure : validation of the MAGGIC heart failure risk score in 51 043 patients from the Swedish Heart Failure Registry
- 2014
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Ingår i: European Journal of Heart Failure. - : Oxford University Press. - 1388-9842 .- 1879-0844. ; 16:2, s. 173-179
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Tidskriftsartikel (refereegranskat)abstract
- AIMS:The aim of this study was to evaluate the performance of a recently developed risk score for mortality in heart failure by external validation in a national heart failure registry.METHODS AND RESULTS:From 13 routinely available patient characteristics, the Meta-analysis Global Group in Chronic Heart Failure (MAGGIC) constructed a risk score for prediction of mortality in heart failure. We included 51 043 patients from the national Swedish Heart Failure Registry and calculated the MAGGIC risk score for each patient. The outcome measure was 3-year mortality. The predicted probability of death obtained from the calculated risk score was compared with the observed 3-year mortality, and model discrimination and calibration were assessed by formal tests and graphical means. The overall 3-year mortality in the study population was 39.4% and the MAGGIC project heart failure risk score predicted mortality was 36.4% (observed to expected ratio: 1.08). Discrimination was excellent overall (C index = 0.741). The difference between the model-predicted and the observed 3-year mortality in the six risk groups varied between 5% and -12%. Calibration plots demonstrated slight overprediction for the lowest risk patients, and underprediction in high risk patients.CONCLUSION:The MAGGIC project heart failure risk score demonstrated an excellent ability to categorize patients in separate risk strata. Although the predicted 3-year mortality risk was higher in low risk groups and lower in high risk groups compared with the observed 3-year mortality in the Swedish Heart Failure Registry, the MAGGIC project heart failure risk score performed well in a large nationwide contemporary external validation cohort.
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| 50. |
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SPECULATE, COLLABORATE, DEFINE - TEXTILE THINKING FOR FUTURE WAYS OF LIVING
- 2017
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Konstnärligt arbete (refereegranskat)abstract
- About the exhibitionHow can we design for the future? In this avant-garde exhibition architects, interaction, fashion and textile designers show their works in progress when they speculate about, collaborate on, and define how to strengthen the foundations of design for more sustainable forms of living. The exhibition Speculate, collaborate, define – textile thinking for future ways of living, is a work in progress by the PhD students in the ArcInTexETN project. ArcInTexETN is an EU-funded training network of early stage researchers exploring new expressions of living through textile thinking. They collaborate in three scales – building, interior, and body – looking into methods for turning current scientific knowledge into the design of new forms of living.With videos as their main medium, the students present different takes on the subject. In “Ahti”, a speculative short film about the first human being born in space, the story is set in the future. It’s 2076 and there is no water left on our planet Earth. Ahti wears the same suit every day, like a second skin. The skin has different properties that protect him and allow him to walk on any surface, levitate, communicate and store energy.Have you heard about the Wolpertinger? It’s a hybrid animal whose appearance evokes the idea that, however different the parts are, they constitute a whole, functioning organism. With the animal as an analogue, a collection of videos are projections of different pieces of work, showing a patchwork of cooperation, exposing the working process of collaborative design.The film “What is interior?” presents an interior landscape, a shifting view of this paradoxical space, narrated by a linguistic review that argues to define the term interior. The film gives an examination of the definitions that frame the term, as well as creating the fleeting textures that shapes it.In addition to the video projections there are also three individual installations. So, bring your nose and your curiosity! This is not only an audio-visual exhibition.
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