| 1. |
- Aldaeus, Fredrik, et al.
(författare)
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Towards a cellulose-based society : current market and consumer trends
- 2017
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Ingår i: The 7th Nordic Wood Biorefinery Conference held in Stockholm, Sweden, 28-30 Mar. 2017. - Stockholm : RISE Bioekonomi. - 9789186018207 ; , s. 1-
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- It has been proposed that the future of the forest industry will involve the traditional value chains combined with the needs and demands of a bio-based economy. A global consumer survey was undertaken, together with interviews and workshops with various representatives through the bio-economy. Sources also included in-depth literature studies and research reviews. Based on this input, several current trends have been identified that will affect the route towards a cellulose-based society. These trends describe the effects of urbanization, consumer behaviour, new business models, material recycling, open innovation and the necessity for early demonstration of new research. Four different but equally plausible scenarios have been identified describing the society and the role of cellulose in 2030, highlighting the role of the wood-based biorefinery.
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| 2. |
- Aldaeus, Fredrik, et al.
(författare)
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Towards a cellulose-based society : current trends, future scenarios, and the role of the wood biorefinery
- 2016
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Ingår i: Proceedings of the 14th European workshop on lignocellulosics and pulp. - 9791090188020 ; , s. 125-127
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- There is a great need to maintain research for a future in which the traditional value chains of the forest industry are combined with the needs and demands of a bio-based economy. In such a future, the pulp mill biorefinery will be a crucial node. In order to map the transformation from a fossil-based society to a cellulose-based society, a global consumer survey has been made. In addition, interviews and workshops with various players throughout the bio-economy field have been accomplished. Several current trends that affect the road to a cellulose-based society have been identified. These trends are describing the effects of urbanization, consumer behaviour, new business models, material recycling, open innovation, and the need for early demonstration of new research. The trends have been combined with uncertainties into a number of plausible scenarios describing the society and the role of cellulose in the year 2030.
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| 3. |
- Bäckström, Erik, 1983-, et al.
(författare)
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Storing keV negative ions for an hour : The lifetime of the metastable 2P1/2 level in 32S−
- 2015
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 114:14
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Tidskriftsartikel (refereegranskat)abstract
- We use a novel electrostatic ion storage ring to measure the radiative lifetime of the upper level in the 3p 5 P 2 o 1/2 →3p 5 P 2 o 3/2 spontaneous radiative decay in S − 32 to be 503±54 sec . This is by orders of magnitude the longest lifetime ever measured in a negatively charged ion. Cryogenic cooling of the storage ring gives a residual-gas pressure of a few times 10 −14 mbar at 13 K and storage of 10 keV sulfur anions for more than an hour. Our experimental results differ by 1.3σ from the only available theoretical prediction.
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| 4. |
- Chartkunchand, Kiattichart C., et al.
(författare)
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Dianion diagnostics in DESIREE : High-sensitivity detection of C-n(2-) from a sputter ion source
- 2018
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Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 89:3
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Tidskriftsartikel (refereegranskat)abstract
- A sputter ion source with a solid graphite target has been used to produce dianions with a focus on carbon cluster dianions, C-n(2-), with n = 7-24. Singly and doubly charged anions from the source were accelerated together to kinetic energies of 10 keV per atomic unit of charge and injected into one of the cryogenic (13 K) ion-beam storage rings of the Double ElectroStatic Ion Ring Experiment facility at Stockholm University. Spontaneous decay of internally hot C-n(2-) dianions injected into the ring yielded C-n(2-) anions with kinetic energies of 20 keV, which were counted with a microchannel plate detector. Mass spectra produced by scanning the magnetic field of a 90 degrees analyzing magnet on the ion injection line reflect the production of internally hot C-7(2-) - C-24(2-) dianions with lifetimes in the range of tens of microseconds to milliseconds. In spite of the high sensitivity of this method, no conclusive evidence of C-6(2-) was found while there was a clear C-7(2-) signal with the expected isotopic distribution. This is consistent with earlier experimental studies and with theoretical predictions. An upper limit is deduced for a C-6(2-) signal that is two orders-of-magnitude smaller than that for C-7(2-). In addition, CnO2- and CnCu2- dianions were detected.
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| 5. |
- Chartkunchand, Kiattichart C., et al.
(författare)
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Radiative lifetimes of the bound excited states of Pt-
- 2016
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Ingår i: Physical Review A - Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 94:3
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Tidskriftsartikel (refereegranskat)abstract
- © 2016 American Physical Society.The intrinsic radiative lifetimes of the 5d106sS1/22 and 5d96s2 D3/22 bound excited states in the platinum anion Pt- have been studied at cryogenic temperatures at the Double ElectroStatic Ion Ring Experiment (DESIREE) facility at Stockholm University. The intrinsic lifetime of the higher-lying 5d106s S1/22 state was measured to be 2.54±0.10s, while only a lifetime in the range of 50-200 ms could be estimated for the 5d96s2 D3/22 fine-structure level. The storage lifetime of the Pt- ion beam was measured to be a little over 15 min at a ring temperature of 13K. The present study reports the lifetime of an atomic negative ion in an excited bound state with an electron configuration different from that of the ground state.
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| 6. |
- Eklund, Gustav, et al.
(författare)
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Cryogenic merged-ion-beam experiments in DESIREE : Final-state-resolved mutual neutralization of Li+ and D-
- 2020
-
Ingår i: Physical Review A: covering atomic, molecular, and optical physics and quantum information. - : American Physical Society (APS). - 2469-9926 .- 2469-9934. ; 102:1
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Tidskriftsartikel (refereegranskat)abstract
- We have developed an experimental technique to study charge-and energy-flow processes in sub-eV collisions between oppositely charged, internally cold, ions of atoms, molecules, and clusters. Two ion beams are stored in separate rings of the cryogenic ion-beam storage facility DESIREE, and merged in a common straight section where a set of biased drift tubes is used to control the center-of-mass collision energy locally in fine steps. Here, we present measurements on mutual neutralization between Li+ and D- where a time-sensitive imaging-detector system is used to measure the three-dimensional distance between the neutral Li and D atoms as they reach the detector. This scheme allows for direct measurements of kinetic-energy releases, and here it reveals separate populations of the 3s state and the (3p + 3d) states in neutral Li while the D atom is left in its ground state 1s. The branching fraction of the 3s final state is measured to be 57.8 +/- 0.7% at a center-of-mass collision energy of 78 +/- 13 meV. The technique paves the way for studies of charge-, energy-, and mass-transfer reactions in single collisions involving molecular and cluster ions in well-defined quantum states.
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| 7. |
- Gatchell, Michael, et al.
(författare)
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Commissioning of the DESIREE storage rings - a new facility for cold ion-ion collisions
- 2014
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Ingår i: XXVIII International Conference on Photonic, Electronic and Atomic Collisions (ICPEAC 2013). - : Institute of Physics (IOP). ; 488:1
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Konferensbidrag (refereegranskat)abstract
- We report on the ongoing commissioning of the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. Beams of atomic carbon anions (C-) and smaller carbon anion molecules (C-2(-), C-3(-), C-4(-) etc.) have been produced in a sputter ion source, accelerated to 10 keV or 20 keV, and stored successfully in the two electrostatic rings. The rings are enclosed in a common vacuum chamber cooled to below 13 Kelvin. The DESIREE facility allows for studies of internally relaxed single isolated atomic, molecular and cluster ions and for collision experiments between cat-and anions down to very low center-of-mass collision energies (meV scale). The total thermal load of the vacuum chamber at this temperature is measured to be 32 W. The decay rates of stored ion beams have two components: a non-exponential component caused by the space charge of the beam itself which dominates at early times and an exponential term from the neutralization of the beam in collisions with residual gas at later times. The residual gas limited storage lifetime of carbon anions in the symmetric ring is over seven minutes while the 1/e lifetime in the asymmetric ring is measured to be about 30 seconds. Although we aim to improve the storage in the second ring, the number of stored ions are now sufficient for many merged beams experiments with positive and negative ions requiring milliseconds to seconds ion storage.
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| 8. |
- Gatchell, Michael, et al.
(författare)
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First results from the Double ElectroStatic Ion-Ring ExpEriment, DESIREE
- 2014
-
Ingår i: XXVIII International Conference on Photonic, Electronic and Atomic Collisions (ICPEAC 2013). - : Institute of Physics (IOP). ; 488
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Konferensbidrag (refereegranskat)abstract
- We have stored the first beams in one of the rings of the double electrostatic ion-storage ring, DESIREE at cryogenic and at room temperature conditions. At cryogenic operations the following parameters are found. Temperature; T= 13K, pressure; p <10(-13) mbar, initial number of stored ions; N > 10(7) and storage lifetime of a C-2(-) beam; tau = 450 S.
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| 9. |
- Hartman, Henrik, et al.
(författare)
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First storage of ion beams in the Double Electrostatic Ion-Ring Experiment : DESIREE
- 2013
-
Ingår i: Review of Scientific Instruments. - : American Institute of Physics (AIP). - 0034-6748 .- 1089-7623. ; 84:5
-
Tidskriftsartikel (refereegranskat)abstract
- We report on the first storage of ion beams in the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. We have produced beams of atomic carbon anions and small carbon anion molecules (Cn-, n = 1, 2, 3, 4) in a sputter ion source. The ion beams were accelerated to 10 keV kinetic energy and stored in an electrostatic ion storage ring enclosed in a vacuum chamber at 13 K. For 10 keV C2- molecular anions we measure the residual-gas limited beam storage lifetime to be 448 s +/- 18 s with two independent detector systems. Using the measured storage lifetimes we estimate that the residual gas pressure is in the 10-14 mbar range. When high current ion beams are injected, the number of stored particles does not follow a single exponential decay law as would be expected for stored particles lost solely due to electron detachment in collision with the residual-gas. Instead, we observe a faster initial decay rate, which we ascribe to the effect of the space charge of the ion beam on the storage capacity.
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| 10. |
- Kamińska, Magdalena, et al.
(författare)
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Lifetime of the bound excited level in Ni
- 2016
-
Ingår i: Physical Review A. - 1050-2947 .- 1094-1622. ; 93:1
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Tidskriftsartikel (refereegranskat)abstract
- The intrinsic lifetime of the upper level in the bound-bound 3d(9) 4s(2) D-2(3/2) -> 3d(9) 4s(2) D-2(5/2) radiative transition in Ni- was measured to be 15.1 +/- 0.4 s. The experiment was performed at cryogenic temperatures in one of the ion-beam storage rings of the Double ElectroStatic Ion Ring ExpEriment facility at Stockholm University. The storage lifetime of the Ni- ion beam was measured to be close to 5 min at a ring temperature of 13 K.
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| 11. |
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| 12. |
- Kristiansson, Moa K., 1989-, et al.
(författare)
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High-precision electron affinity of oxygen
- 2022
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Negative ions are important in many areas of science and technology, e.g., in interstellar chemistry, for accelerator-based radionuclide dating, and in anti-matter research. They are unique quantum systems where electron-correlation effects govern their properties. Atomic anions are loosely bound systems, which with very few exceptions lack optically allowed transitions. This limits prospects for high-resolution spectroscopy, and related negative-ion detection methods. Here, we present a method to measure negative ion binding energies with an order of magnitude higher precision than what has been possible before. By laser-manipulation of quantum-state populations, we are able to strongly reduce the background from photodetachment of excited states using a cryogenic electrostatic ion-beam storage ring where keV ion beams can circulate for up to hours. The method is applicable to negative ions in general and here we report an electron affinity of 1.461 112 972(87) eV for O-16. High-precision measurements are useful to find isotopic shifts and electron correlation. Here the authors measure electron affinity and hyperfine splitting of atomic oxygen with higher precision than previous studies.
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| 13. |
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| 14. |
- Mattsson, C. Mikael, et al.
(författare)
-
Träna för en svensk klassiker och andra långlopp
- 2015
-
Bok (populärvet., debatt m.m.)abstract
- Förbered dig rätt inför långlopp. Att under ett år genomföra Vätternrundan, Vansbrosimningen, Lidingöloppet och Engelbrektsloppet/Vasaloppet, är ett av de mest populära sätten att skörda frukten av sin träning och nå sitt mål. För att lyckas krävs goda förberedelser, och ju bättre förberedd du är desto mer positiv blir upplevelsen. Innehållet i denna bok är en fördjupning av samlad kunskap och erfarenhet inom simning, cykel, löpning, längdskidåkning och triathlon samt hur man på bästa sätt kombinerar de olika idrotterna – deras olika moment – i träning och tävling. Här hittar du också kapitel om träningslära, idrottsnutrition, mental träning, förebyggande av idrottsskador och träningsplanering för att öka förståelsen av vad som påverkar en idrottsprestation.Extramaterial på webbplatsen: För att kunna erbjuda mer än vad som ryms i en bok, har vi också skapat en webbplats. Med hjälp av koden som följer med i boken kan du registrera dig för att ta del av fördjupande texter, träningsprogram och kostupplägg, övningar och intressanta länkar.(Text från förlaget)
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| 15. |
- Ovegård, Erik, et al.
(författare)
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Operational Guidance with Respect to Pure Loss of Stability and Parametric Rolling
- 2012
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Ingår i: Proceedings of the 11<sup>th</sup> International Conference on the Stability of Ships and Ocean Vehicles (STAB2012).
-
Konferensbidrag (refereegranskat)abstract
- This paper reviews two previously presented simplified methods for assessment of pure loss of stability and parametric rolling based on linear signal theory. The methods are evaluated in relation to full-scale incidents and time-domain simulations. Underlying assumptions and tuning of the critical levels in the simplified methods with reference to time-domain simulations is discussed. Given proper tuning the methods are concluded to provide a feasible basis for ship specific on-board operational guidance.
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| 16. |
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| 17. |
- Rosén, Anders, et al.
(författare)
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Experience from Parametric Rolling of Ships
- 2012
-
Ingår i: Parametric Resonance in Dynamical Systems. - New York, NY : Springer. - 9781461410423 ; , s. 147-165
-
Bokkapitel (refereegranskat)abstract
- This chapter reviews three recent full-scale events with parametric rolling for Ro–Ro Large Car and Truck Carriers (LCTC). The events represent three principally different modes of parametric rolling: principal parametric resonance where the period of encounter is half of the roll natural period in following seas (I) and in head seas (II), and fundamental parametric resonance where the period of encounter coincides with the roll natural period in following seas (III). Roll motion, course, and speed recorded during the events are presented and analyzed together with the present weather situation based on recordings, forecasts, and re-analysis. Different aspects of on-board operational guidance for assisting crews in avoiding parametric rolling are discussed in relation to the presented events. Involved complexities and considerations that are normally not included in well defined model tests or numerical simulations are exposed.
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| 18. |
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| 19. |
- Schmidt, Henning, et al.
(författare)
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DESIREE as a new tool for interstellar ion chemistry
- 2008
-
Ingår i: International Journal of Astrobiology. - 1473-5504 .- 1475-3006. ; 7:3-4, s. 205-208
-
Tidskriftsartikel (refereegranskat)abstract
- A novel cryogenic electrostatic storage device consisting of two ion-beam storage rings with a common straight section for studies of interactions between oppositely charged ions at low and well-defined relative velocities is under construction at Stockholm University. Here we consider the prospect of using this new tool to measure cross-sections and rate coefficients for mutual neutralization reactions of importance in interstellar ion chemistry in general and specifically in cosmic pre-biotic ion chemistry.
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| 20. |
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| 21. |
- Schmidt-May, Alice F., 1988-, et al.
(författare)
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State-resolved mutual neutralization of 16O+ with 1H− and 2H− at collision energies below 100 meV
- 2024
-
Ingår i: Physical Review A: covering atomic, molecular, and optical physics and quantum information. - 2469-9926 .- 2469-9934. ; 109:5
-
Tidskriftsartikel (refereegranskat)abstract
- We measured the product-state distribution and its dependence on the hydrogen isotope for the mutual neutralization between 16O+ and 1,2H− at the double electrostatic ion-beam storage ring DESIREE for center-of-mass collision energies below 100 meV. We find at least six product channels into ground-state hydrogen and oxygen in different excited states. The majority of oxygen products populate terms corresponding to 2?22?3(4?∘)4? with 5S∘ as the main reaction product. We also observe product channels into terms corresponding to 2?22?3(4?)3?. Collisions with the heavier hydrogen isotope yield a branching into these lower excited states smaller than collisions with 1H−. The observed reaction products agree with the theoretical predictions. The detailed branching fractions, however, differ between the theoretical results, and none of them fully agree with the experiment.
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| 22. |
- Thomas, Richard D., et al.
(författare)
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DESIREE : Physics with cold stored ion beams
- 2015
-
Ingår i: DR2013. - : EDP Sciences. ; 84, s. 01004-01004
-
Konferensbidrag (refereegranskat)abstract
- Here we will briefly describe the commissioning of the Double ElectroStatic Ion Ring ExpEriment (DESIREE) facility at Stockholm University, Sweden. This device uses purely electrostatic focussing and deflection elements and allows ion beams of opposite charge to be confined under extreme high vacuum and cryogenic conditions in separate rings and then merged over a common straight section. This apparatus allows for studies of interactions between cations and anions at very low and well-defined centre-of-mass energies (down to a few meV) and at very low internal temperatures (down to a few K).
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| 23. |
- Thomas, Richard D., et al.
(författare)
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The double electrostatic ion ring experiment : A unique cryogenic electrostatic storage ring for merged ion-beams studies
- 2011
-
Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 82:6, s. 065112-
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Tidskriftsartikel (refereegranskat)abstract
- We describe the design of a novel type of storage device currently under construction at Stockholm University, Sweden, using purely electrostatic focussing and deflection elements, in which ion beams of opposite charges are confined under extreme high vacuum cryogenic conditions in separate rings and merged over a common straight section. The construction of this double electrostatic ion ring experiment uniquely allows for studies of interactions between cations and anions at low and well-defined internal temperatures and centre-of-mass collision energies down to about 10 K and 10 meV, respectively. Position sensitive multi-hit detector systems have been extensively tested and proven to work in cryogenic environments and these will be used to measure correlations between reaction products in, for example, electron-transfer processes. The technical advantages of using purely electrostatic ion storage devices over magnetic ones are many, but the most relevant are: electrostatic elements which are more compact and easier to construct; remanent fields, hysteresis, and eddy-currents, which are of concern in magnetic devices, are no longer relevant; and electrical fields required to control the orbit of the ions are not only much easier to create and control than the corresponding magnetic fields, they also set no upper mass limit on the ions that can be stored. These technical differences are a boon to new areas of fundamental experimental research, not only in atomic and molecular physics but also in the boundaries of these fields with chemistry and biology. For examples, studies of interactions with internally cold molecular ions will be particular useful for applications in astrophysics, while studies of solvated ionic clusters will be of relevance to aeronomy and biology.
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| 24. |
- Alehagen, Urban, et al.
(författare)
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Cardiovascular mortality and N-terminal-proBNP reduced after combined selenium and coenzyme Q10 supplementation : a 5-year prospective randomized double-blind placebo-controlled trial among elderly Swedish citizens
- 2013
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Ingår i: International Journal of Cardiology. - : Elsevier BV. - 0167-5273 .- 1874-1754. ; 167:5, s. 1860-1866
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundSelenium and coenzyme Q10 are essential for the cell. Low cardiac contents of selenium and coenzyme Q10 have been shown in patients with cardiomyopathy, but inconsistent results are published on the effect of supplementation of the two components separately. A vital relationship exists between the two substances to obtain optimal function of the cell. However, reports on combined supplements are lacking.MethodsA 5-year prospective randomized double-blind placebo-controlled trial among Swedish citizens aged 70 to 88 was performed in 443 participants given combined supplementation of selenium and coenzyme Q10 or a placebo. Clinical examinations, echocardiography and biomarker measurements were performed. Participants were monitored every 6th month throughout the intervention.The cardiac biomarker N-terminal proBNP (NT-proBNP) and echocardiographic changes were monitored and mortalities were registered. End-points of mortality were evaluated by Kaplan–Meier plots and Cox proportional hazard ratios were adjusted for potential confounding factors. Intention-to-treat and per-protocol analyses were applied.ResultsDuring a follow up time of 5.2 years a significant reduction of cardiovascular mortality was found in the active treatment group vs. the placebo group (5.9% vs. 12.6%; P = 0.015). NT-proBNP levels were significantly lower in the active group compared with the placebo group (mean values: 214 ng/L vs. 302 ng/L at 48 months; P = 0.014). In echocardiography a significant better cardiac function score was found in the active supplementation compared to the placebo group (P = 0.03).ConclusionLong-term supplementation of selenium/coenzyme Q10 reduces cardiovascular mortality. The positive effects could also be seen in NT-proBNP levels and on echocardiography.
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| 25. |
- Alehagen, Urban, et al.
(författare)
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Relatively high mortality risk in elderly Swedish subjects with low selenium status
- 2016
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Ingår i: European Journal of Clinical Nutrition. - : Nature Publishing Group. - 0954-3007 .- 1476-5640. ; 70:1, s. 91-96
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Tidskriftsartikel (refereegranskat)abstract
- Background/Objectives: The daily dietary intake of selenium (Se), an essential trace element, is still low in Sweden in spite of decades of nutritional information campaigns and the effect of this on the public health is presently not well known. The objective of this study was to determine the serum Se levels in an elderly Swedish population and to analyze whether a low Se status had any influence on mortality.Subjects/Methods: Six-hundred sixty-eight (n=668) elderly participants were invited from a municipality and evaluated in an observational study. Individuals were followed for 6.8 years and Se levels were re-evaluated in 98 individuals after 48 months. Clinical examination of all individuals included functional classification, echocardiography, electrocardiogram and serum Se measurement. All mortality was registered and endpoints of mortality were assessed by Kaplan–Meier plots, and Cox proportional hazard ratios adjusted for potential confounding factors were calculated.Results: The mean serum Se level of the study population (n=668) was 67.1 μg/l, corresponding to relatively low Se intake. After adjustment for male gender, smoking, ischemic heart disease, diabetes, chronic obstructive pulmonary disease and impaired heart function, persons with serum Se in the lowest quartile had 43% (95% confidence interval (CI): 1.02–2.00) and 56% (95% CI: 1.03–2.36) increased risk for all-cause and cardiovascular mortality, respectively. The result was not driven by inflammatory effects on Se concentration in serum.Conclusion: The mean serum Se concentration in an elderly Swedish population was 67.1 μg/l, which is below the physiological saturation level for several selenoprotein enzymes. This result may suggest the value of modest Se supplementation in order to improve the health of the Swedish population.
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| 26. |
- Alerstam, Thomas, et al.
(författare)
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A polar system of intercontinental bird migration
- 2007
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Ingår i: Royal Society of London. Proceedings B. Biological Sciences. - : The Royal Society. - 1471-2954. ; 274:1625, s. 2523-2530
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Tidskriftsartikel (refereegranskat)abstract
- Studies of birdmigration in the Beringia region of Alaska and eastern Siberia are of special interest for revealing the importance of bird migration between Eurasia and North America, for evaluating orientation principles used by the birds at polar latitudes and for understanding the evolutionary implications of intercontinental migratory connectivity among birds as well as their parasites. We used tracking radar placed onboard the ice-breaker Oden to register bird migratory flights from 30 July to 19 August 2005 and we encountered extensive birdmigration in the whole Beringia range from latitude 64 degrees N in Bering Strait up to latitude 75 degrees N far north of Wrangel Island, with eastward flights making up 79% of all track directions. The results from Beringia were used in combination with radar studies from the Arctic Ocean north of Siberia and in the Beaufort Sea to make a reconstruction of a major Siberian-American birdmigration system in a wide Arctic sector between longitudes 1108 E and 130 degrees W, spanning one-third of the entire circumpolar circle. This system was estimated to involve more than 2 million birds, mainly shorebirds, terns and skuas, flying across the Arctic Ocean at mean altitudes exceeding 1 km (maximum altitudes 3-5 km). Great circle orientation provided a significantly better fit with observed flight directions at 20 different sites and areas than constant geographical compass orientation. The long flights over the sea spanned 40-80 degrees of longitude, corresponding to distances and durations of 1400-2600 km and 26-48 hours, respectively. The birds continued from this eastward migration system over the Arctic Ocean into several different flyway systems at the American continents and the Pacific Ocean. Minimization of distances between tundra breeding sectors and northerly stopover sites, in combination with the Beringia glacial refugium and colonization history, seemed to be important for the evolution of this major polar bird migration system.
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| 27. |
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| 28. |
- Alerstam, Thomas, et al.
(författare)
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Flight speeds among bird species : allometric and phylogenetic effects.
- 2007
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Ingår i: PLoS biology. - : Public Library of Science (PLoS). - 1544-9173 .- 1545-7885. ; 5:8, s. e197-
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Tidskriftsartikel (refereegranskat)abstract
- Flight speed is expected to increase with mass and wing loading among flying animals and aircraft for fundamental aerodynamic reasons. Assuming geometrical and dynamical similarity, cruising flight speed is predicted to vary as (body mass)(1/6) and (wing loading)(1/2) among bird species. To test these scaling rules and the general importance of mass and wing loading for bird flight speeds, we used tracking radar to measure flapping flight speeds of individuals or flocks of migrating birds visually identified to species as well as their altitude and winds at the altitudes where the birds were flying. Equivalent airspeeds (airspeeds corrected to sea level air density, Ue) of 138 species, ranging 0.01-10 kg in mass, were analysed in relation to biometry and phylogeny. Scaling exponents in relation to mass and wing loading were significantly smaller than predicted (about 0.12 and 0.32, respectively, with similar results for analyses based on species and independent phylogenetic contrasts). These low scaling exponents may be the result of evolutionary restrictions on bird flight-speed range, counteracting too slow flight speeds among species with low wing loading and too fast speeds among species with high wing loading. This compression of speed range is partly attained through geometric differences, with aspect ratio showing a positive relationship with body mass and wing loading, but additional factors are required to fully explain the small scaling exponent of Ue in relation to wing loading. Furthermore, mass and wing loading accounted for only a limited proportion of the variation in Ue. Phylogeny was a powerful factor, in combination with wing loading, to account for the variation in Ue. These results demonstrate that functional flight adaptations and constraints associated with different evolutionary lineages have an important influence on cruising flapping flight speed that goes beyond the general aerodynamic scaling effects of mass and wing loading.
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| 29. |
- Alerstam, Thomas, et al.
(författare)
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Great-Circle Migration Of Arctic Passerines
- 2008
-
Ingår i: The Auk. - : Oxford University Press (OUP). - 0004-8038 .- 1938-4254. ; 125:4, s. 831-838
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Tidskriftsartikel (refereegranskat)abstract
- Birds can save distance and time on their migratory journeys by following great circles rather than rhumblines, but great-circle routes require more complex orientation with changing courses. Flight directions at different places along the route and in relation to the destination can be used to test whether birds migrate along great circles or rhumblines. Such data have indicated great-circle migration among shorebirds at high latitudes, but no critical tests have been made for passerines. Using tracking radar on board the icebreaker Oden in August 2005, we recorded westerly flight directions of passerine migrants over the Chukchi Sea. The main sector of migratory directions was 237-311 degrees centered oil a mean heading direction of 274 degrees. The most likely species to participate in this westward trans-Beringia migration, mainly departing from Alaska, were Eastern Yellow Wagtail (Motacilla Ischutschensis), Arctic Warbler (Phylloscopus borealis kennicotti), Northern Wheatear (Oenanthe oenanthe), and Bluethroat (Luscinia svecica); all except the Bluethroat were recorded from the ship. Observed flight directions agreed with predicted great-circle courses but not with rhumbline courses for three of these four species with winter quarters in Southeast Asia; no definite conclusion could be drawn for the Northern Wheatear (wintering in East Africa). These results support great-circle migration among passerines traveling between Alaska and Old World winter quarters, though the long-distance precision and orientation mechanisms are Still unknown. The relative importance of different evolutionary causes-such as circumvention of geographic barriers, retracing of ancient colonization ways, or distance reduction by great-circle migration-to complex bird migration routes with changing courses remains to be understood. Received 24 August 2007, accepted 6 March 2008.
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| 30. |
- Altahr-Cederberg, Camilla, et al.
(författare)
-
Vad tänker du på, när jag säger energieffektivisering i kulturhistoriskt värdefulla byggnader?
- 2010
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Rapporten innehåller en sammanställning av intervjuer med byggnadsantikvarier på länsstyrelser och stift angående energieffektivisering i kulturhistoriskt värdefulla byggnader. Intervjuerna har utförs inom ett projekt på RAÄ som bedrivs inom forskningsprogrammet Spara och Bevara, energieffektivisering i kulturhistoriskt värdefulla byggnader, som finansieras av Energimyndigheten, Riksantikvarieämbetet och Svenska kyrkan.
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| 31. |
- Andersson-Sköld, Yvonne, 1957-, et al.
(författare)
-
Metod och effektsamband för identifiering, bedömning och prioritering av åtgärder för klimatanpassning av vägar och järnvägar : en förstudie
- 2019
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Syftet med den förstudie som redovisas i denna rapport var att ta fram grunden för en metod till stöd för Trafikverkets planering av klimatanpassningsåtgärder för väg och järnväg. Rapporten fokuserar på effektsamband för identifiering, bedömning och prioritering av åtgärder för klimatanpassning av vägar och järnvägar. Metoden och resultaten som presenteras i denna rapport är baserade på litteraturstudier och intervjuer med experter inom väg och järnvägsområdet.I rapporten beaktas de konsekvenser och risker som förväntas uppkomma till följd av klimatrelaterade händelser, exempelvis den konsekvens som uppstår vid en specifik klimatrelaterad händelse, såsom de konsekvenser som uppstår vid ett specifikt översvämningsdjup, och åtgärder som kan vidtas för att minska sannolikheten för negativa konsekvenser samt de negativa konsekvenserna i sig.För att bedöma eller beräkna hur stor risken är krävs kännedom om sannolikheten för att en viss klimatrelaterad händelse ska inträffa under en given period, samt storlek och typ av skada. Skadekostnaden är summan av försenings- och/eller avstängningskostnad som kan innefatta omledningskostnader och kostnader för byte mellan transportslag med mera samt återställningskostnad. Dessutom ingår även skador på människor och miljön som kan uppkomma till följd av händelsen, till exempel vid skred.
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| 32. |
- Azasu, S, et al.
(författare)
-
CDIO in Africa
- 2019
-
Ingår i: <em>Proceedings of the 15th International CDIO Conference</em>.
-
Konferensbidrag (refereegranskat)
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| 33. |
- Begovic, Ermina, et al.
(författare)
-
Experimental modelling of local structure responses for high-speed planing craft in waves
- 2020
-
Ingår i: Ocean Engineering. - : Elsevier Ltd. - 0029-8018 .- 1873-5258. ; 216
-
Tidskriftsartikel (refereegranskat)abstract
- The modelling of planing craft dynamics in waves and related fluid-structure interaction is a hard challenge due to the highly nonlinear, transient and stochastic nature of the whole process. This paper explores the prospectives of detailed experimental modelling of the local structure responses for high-speed planing craft in waves. A novel experimental setup is presented where a well-defined model structure is integrated into the hull bottom of a typical planing craft model. The model is instrumented for measuring strains in the model structure, related slamming pressures, craft rigid body motions and accelerations. The experimental setup is thoroughly described and motivated and crucial aspects of the setup are verified through testing in idealized static loading conditions and by modal analysis. The capabilities of the experimental setup are demonstrated through systematic experiments in regular waves. The most indicative results are presented and discussed in relation to corresponding results from time-domain simulations The presented experimental modelling approach is concluded to enable uniquely detailed studies of the complete slamming related fluid-structure interaction process and provides a good tool for further research and development towards establishment of first principles-based methods for hydrodynamic and structure design of high-speed planing craft.
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| 34. |
- Benson, Mikael, et al.
(författare)
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Intrathecal immunoglobulin production and minor motor seizures
- 1987
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Ingår i: Acta Paediatrica. - : Wiley-Blackwell. - 0803-5253 .- 1651-2227. ; 76:1, s. 147-150
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Tidskriftsartikel (refereegranskat)abstract
- Five infants with idiopathic infantile minor motor seizures had an elevated immunoglobulin G (IgG) index ((cerebrospinal fluid IgG/serum IgG):(cerebrospinal fluid albumin/serum albumin)). The infants had prolonged prodromal symptoms, and bad prognosis. It is suggested that immunological mechanisms may contribute to the pathophysiology in certain cases of infantile spasms.
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| 35. |
- Evans, MR, et al.
(författare)
-
How do birds' tails work? Delta-wing theory fails to predict tail shape during flight
- 2002
-
Ingår i: Royal Society of London. Proceedings B. Biological Sciences. - : The Royal Society. - 1471-2954. ; 269:1495, s. 1053-1057
-
Tidskriftsartikel (refereegranskat)abstract
- Birds appear to use their tails during flight, but until recently the aerodynamic role that tails fulfil was largely unknown. In recent years delta-wing theory, devised to predict the aerodynamics of high-performance aircraft, has been applied to the tails of birds and has been successful in providing a model for the aerodynamics of a birds tail. This theory now provides the conventional explanation for how birds tails work. A delta-wing theory (slender-wing theory) has been used, as part of a variable-geometry model to predict how tail and wing shape should vary during flight at different airspeeds. We tested these predictions using barn swallows flying in a wind tunnel. We show that the predictions are not quantitatively well supported. This suggests that a new theory or a modified version of delta-wing theory is needed to adequately explain the way in which morphology varies during flight.
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| 36. |
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| 37. |
- Godang, Kristin, et al.
(författare)
-
The effect of surgery on fat mass, lipid and glucose metabolism in mild primary hyperparathyroidism
- 2018
-
Ingår i: Endocrine connections. - 2049-3614. ; 7:8, s. 941-948
-
Tidskriftsartikel (refereegranskat)abstract
- Mild primary hyperparathyroidism has been associated with increased body fat mass and unfavorable cardiovascular risk factors.To assess the effect of parathyroidectomy on fat mass, glucose and lipid metabolism.119 patients previously randomized to observation (OBS; n=58) or parathyroidectomy (PTX; n=61) within the Scandinavian Investigation of Primary Hyperparathyroidism (SIPH) trial, an open randomized multicenter study, were included. Main outcome measures for this study were the differences in fat mass, markers for lipid and glucose metabolism between OBS and PTX 5 years after randomization.In the OBS group, total cholesterol (Total-C) decreased from mean 5.9 (±1.1) to 5.6 (±1.0)mmol/L (P=0.037) and LDL cholesterol (LDL-C) decreased from 3.7 (±1.0) to 3.3 (±0.9)mmol/L (P=0.010). In the PTX group, the Total-C and LDL-C remained unchanged resulting in a significant between-group difference over time (P=0.013 and P=0.026, respectively). This difference was driven by patients who started with lipid-lowering medication during the study period (OBS: 5; PTX: 1). There was an increase in trunk fat mass in the OBS group, but no between-group differences over time. Mean 25(OH) vitamin D increased in the PTX group (P<0.001), but did not change in the OBS group. No difference in parameters of glucose metabolism was detected.In mild PHPT, the measured metabolic and cardiovascular risk factors were not modified by PTX. Observation seems safe and cardiovascular risk reduction should not be regarded as a separate indication for parathyroidectomy based on the results from this study.
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| 38. |
- Gustafsson, Håkan, et al.
(författare)
-
Fe(III) distribution varies substantially within and between atherosclerotic plaques
- 2014
-
Ingår i: Magnetic Resonance in Medicine. - United States : John Wiley & Sons. - 0740-3194 .- 1522-2594. ; 2:71, s. 885-892
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE:Vulnerable atherosclerotic plaques are structurally weak and prone to rupture, presumably due to local oxidative stress. Redox active iron is linked to oxidative stress and the aim of this study was to investigate the distribution of Fe(III) in carotid plaques and its relation to vulnerability for rupture.METHODS:Atherosclerotic plaques from 10 patients (three asymptomatic and seven symptomatic) were investigated. Plaque vulnerability was classified using ultrasound and immunohistochemistry and correlated to Fe(III) measured by electron paramagnetic resonance spectroscopy.RESULTS:Large intra-plaque Fe(III) variations were found. Plaques from symptomatic patients had a higher Fe(III) concentration as compared with asymptomatic plaques (0.36 ± 0.21 vs. 0.06 ± 0.04 nmol Fe(III)/mg tissue, P < 0.05, in sections adjoining narrowest part of the plaques). All but one plaque from symptomatic patients showed signs of cap rupture. No plaque from asymptomatic patients showed signs of cap rupture. There was a significant increase in cap macrophages in plaques from symptomatic patients compared with asymptomatic patients (31 ± 11% vs. 2.3 ± 2.3%, P < 0.01).CONCLUSION:Fe(III) distribution varies substantially within atherosclerotic plaques. Plaques from symptomatic patients had significantly higher concentrations of Fe(III), signs of cap rupture and increased cap macrophage activity.
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| 39. |
- Hamawandi, Bejan, PhD, et al.
(författare)
-
Composition Tuning of Nanostructured Binary Copper Selenides through Rapid Chemical Synthesis and their Thermoelectric Property Evaluation
- 2020
-
Ingår i: Nanomaterials. - : MDPI. - 2079-4991. ; 10:5
-
Tidskriftsartikel (refereegranskat)abstract
- Reduced energy consumption and environmentally friendly, abundant constituents are gaining more attention for the synthesis of energy materials. A rapid, highly scalable, and process-temperature-sensitive solution synthesis route is demonstrated for the fabrication of thermoelectric Cu2−xSe. The process relies on readily available precursors and microwave-assisted thermolysis, which is sensitive to reaction conditions; yielding Cu1.8Se at 200 °C and Cu2Se at 250 °C within 6–8 min reaction time. Transmission electron microscopy (TEM) revealed crystalline nature of as-made particles with irregular truncated morphology, which exhibit a high phase purity as identified by X-ray powder diffraction (XRPD) analysis. Temperature-dependent transport properties were characterized via electrical conductivity, Seebeck coefficient, and thermal diffusivity measurements. Subsequent to spark plasma sintering, pure Cu1.8Se exhibited highly compacted and oriented grains that were similar in size in comparison to Cu2Se, which led to its high electrical and low thermal conductivity, reaching a very high power-factor (24 µW/K−2cm−1). Density-of-states (DOS) calculations confirm the observed trends in electronic properties of the material, where Cu-deficient phase exhibits metallic character. The TE figure of merit (ZT) was estimated for the materials, demonstrating an unprecedentedly high ZT at 875 K of 2.1 for Cu1.8Se sample, followed by 1.9 for Cu2Se. Synthetic and processing methods presented in this work enable large-scale production of TE materials and components for niche applications.
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| 40. |
- Hedenström, Anders, et al.
(författare)
-
Body frontal area in passerine birds
- 2003
-
Ingår i: Journal of Avian Biology. - 0908-8857. ; 34:2, s. 159-162
-
Tidskriftsartikel (refereegranskat)abstract
- Projected body frontal area is used when estimating the parasite drag of bird flight. We investigated the relationship between projected frontal area and body mass among passerine birds, and compared it with an equation based on waterfowl and raptors, which is used as default procedure in a widespread software package for flight performance calculations. The allometric equation based on waterfowl/raptors underestimates the frontal area compared to the passerine equation presented here. Consequently, revising the actual frontal areas of small birds will concomitantly change the values of the parasite drag coefficient. We suggest that the new equation S-b = 0.0129m(B)(0.61) (m(2)) where m(B) is body mass (kg) should be used when a value of frontal area is needed for passerines.
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| 41. |
- Hedenström, Anders, et al.
(författare)
-
Flight performance during hunting excursions in Eleonora's falcon Falco eleonorae
- 1999
-
Ingår i: Journal of Experimental Biology. - : The Company of Biologists. - 1477-9145 .- 0022-0949. ; 202:15, s. 2029-2039
-
Tidskriftsartikel (refereegranskat)abstract
- Among birds, falcons are high-performance flyers, in many cases adapted for aerial hunting and hence suitable targets for investigating limits to flight performance. Using an optical range finder, we measured flight tracks of Eleonoras falcon (Falco eleonorae), a species breeding in the Mediterranean region and specialised for hunting autumn passage bird migrants, when commuting between their nesting colony and offshore hunting areas (straight transportation flight) and when searching for prey (transecting and searching flight). Airspeed during searching flight was significantly slower than during straight transportation and transecting flight, but there was no significant difference in airspeed between the latter two flight modes. Straight transportation flight was significantly faster than predicted minimum power speed. Also, during straight transportation flight, the falcons responded to head- and tailwinds by increasing their airspeed when flying into the wind. However, they did not show any significant airspeed adjustments with respect to the angle between the track and the heading, as would be expected in birds trying to maintain a constant track direction. Mean sustainable climb rate (during (greater than or equal to) 240 s) was 1.4+/-0.31 m s-1 (mean +/- s.d., N=13), which is rather a high rate for a bird the size of an Eleonoras falcon. The climb rate was used to calculate maximum load-carrying capacity and maximum sustained horizontal flapping flight speed. The mean wingbeat frequency during powered climbing flight was 4.68 Hz, which was used to estimate the mass-specific muscle work. When falcons were leaving the colony for offshore hunting, they gained altitude by slope-soaring when there was an onshore wind. We formulated a simple criterion for the required gliding-flight rate of climb during an initial slope-soaring episode when minimizing the energy cost of reaching a certain altitude far out over the sea (which is where the prey is to be found). This climb rate was 0.36 m s-1, and our observations indicated that the falcons experienced climb rates above this value when soaring in slope-lift.
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| 42. |
- Hedenström, Anders, et al.
(författare)
-
Magnetic resonance imaging versus chemical fat extraction in a small passerine, the willow warbler Phylloscopus trochilus: A fat-score based statistical comparison
- 2009
-
Ingår i: Journal of Avian Biology. - 0908-8857. ; 40:4, s. 457-460
-
Tidskriftsartikel (refereegranskat)abstract
- Abstract in UndeterminedThe amount of fat of a bird is a fundamental metric commonly used by avian biologists in studies of migration, winter energy management and condition. The methods used for estimating fat content range from simply measuring body mass and subtracting the estimated lean mass, visual scoring of subcutaneous fat deposits, to destructive extraction using a Soxhlet apparatus. We used magnetic resonance imaging (MRI) for non-invasive estimation of fat content in willow warblers Phylloscopus trochilus. According to an indirect comparison, made using a standardized fat scoring system as a common measure, the MRI method gave very similar fat amount as Soxhlet extraction and we discuss advantages of using MRI over alternative methods. It was also shown that the commonly used fat scoring system yielded a nonlinear relationship between fat mass and fat score.
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| 43. |
- Hedenström, Anders, et al.
(författare)
-
Predator versus prey: on aerial hunting and escape strategies in birds
- 2001
-
Ingår i: Behavioral Ecology. - : Oxford University Press (OUP). - 1045-2249 .- 1465-7279. ; 12:2, s. 150-156
-
Tidskriftsartikel (refereegranskat)abstract
- Predator and prey attack-escape performance is Likely to be the outcome of an evolutionary arms race, Predatory birds are typically larger than their prey suggesting different flight performances. We analyze three idealized attack-escape situations between predatory and prey birds: climbing flight escape, horizontal speeding, and turning and escape by diving. Generally a smaller bird will outclimb a larger predator and hence outclimbing should be a common escape strategy. However, some predators such as the Eleonora's falcon (Falco eleonorae) has a very high rate of climb for its size. Prey species with an equal or higher capacity to climb fast, such as the swift Apus apus, usually adopt climbing escape when attacked by Eleonora's falcons. To analyze the outcome of the turning gambit between predator and prey we use a Howland diagram, where the relative linear top speeds and minimum turning radii of prey and predator define the escape and danger zones. Applied to die Eleonora's falcon and some potential prey species, this analysis indicates that the falcon usually wins against the example prey species; that is, the prey will be captured. Level maneuvering hunting is the most common strategy seen in Eleonora's falcons. To avoid capture via use of this strategy by a predator, the prey should be able to initiate tight turns at high linear speed, which is facilitated by a low wing loading (weight per unit of wing area). High diving speed is favored by large size. Lf close enough to safe cover, a prey might still opt for a vertical dive to escape in spite of lower terminal diving speed than that of the predator. On the basis of aerodynamic considerations we discuss escape flight strategies in birds in relation to morphological adaptations.
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| 44. |
- Hedenström, Anders, et al.
(författare)
-
Radar Observations of Arctic Bird Migration in the Beringia Region
- 2009
-
Ingår i: Arctic. - 0004-0843. ; 62:1, s. 25-37
-
Tidskriftsartikel (refereegranskat)abstract
- Bird migration was recorded by tracking radar and visual observations in the Beringia region. The data were subdivided into seven areas extending from north of Wrangel Island southeastward toward the Bering Strait and then northwestward off the coast of Alaska to Point Barrow. The studies, which took place during a ship-based expedition between 30 July and 19 August 2005, recorded a total of 557 tracks (average duration 120 seconds) of bird flocks or individuals on post-breeding migration. The dominant eastward-flying flocks were likely composed of shorebirds on their way from breeding areas in central or eastern Siberia to intermediate stopovers and final destinations in North and South America. The courses were more southerly into the Bering Strait, possibly because of topographical influence. At two areas, the Chukchi Sea and Koluchinskaya Bay, there was also a westward component of migrants. At the Chukchi Sea these were almost certainly passerine birds migrating from Alaska to wintering areas in Asia and Africa, while at Koluchinskaya Bay, king ciders on molt migration could represent an important part of the westward component. The overall mean altitude of flights was 1157 m, and flight altitude was positively correlated with latitude. The mean ground speed was 15.9 m/s and the mean airspeed was 14.1 m/s, indicating that on average the birds were experiencing a small tail wind component. The airspeed was a function of the tail wind component and the vertical speed; altitude and the side wind component did not contribute significantly to variation in airspeed in this data set. Comparing these results with similar data obtained from Siberia and Canada, we concluded that Beringia is a migration hotspot where intense bird migration crosses between Asia and Alaska in both directions.
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| 45. |
- Hedenström, Anders, et al.
(författare)
-
Vortex wakes generated by robins Erithacus rubecula during free flight in a wind tunnel
- 2006
-
Ingår i: Journal of the Royal Society Interface. - : The Royal Society. - 1742-5662 .- 1742-5689. ; 3:7, s. 263-276
-
Tidskriftsartikel (refereegranskat)abstract
- The wakes of two individual robins were measured in digital particle image velocimetry (DPIV) experiments conducted in the Lund wind tunnel. Wake measurements were compared with each other, and with previous studies in the same facility. There was no significant individual variation in any of the measured quantities. Qualitatively, the wake structure and its gradual variation with flight speed were exactly as previously measured for the thrush nightingale. A procedure that accounts for the disparate sources of circulation spread over the complex wake structure nevertheless can account for the vertical momentum flux required to support the weight, and an example calculation is given for estimating drag from the components of horizontal momentum flux (whose net value is zero). The measured circulations of the largest structures in the wake can be predicted quite well by simple models, and expressions are given to predict these and other measurable quantities in future bird flight experiments.
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| 46. |
- Hedenström, Anders, et al.
(författare)
-
Vortex wakes of birds: recent developments using digital particle image velocimetry in a wind tunnel
- 2006
-
Ingår i: Animal Biology. - : Brill. - 1570-7555 .- 1570-7563. ; 56:4, s. 535-549
-
Tidskriftsartikel (refereegranskat)abstract
- A flying animal generates a trail of wake vortices that contain information about the time history and magnitude of aerodynamic forces developed on the wings and body. Methods for visualising and recording wake vortices have been developed, allowing quantitative measurements by digital particle image velocimetry (DPIV). Results from DPIV experiments in a wind tunnel are presented for four passerine species of differing size and morphology. The normalised vorticity and its integrated quantity, circulation (Gamma) both decline gradually with increasing flight speed. The measured circulations are successfully explained by a simple aerodynamic model where a normalised circulation, Gamma/Uc, represents half the time-averaged lift coefficient, which is > 2 at 4 m s(-1) for a thrush nightingale.
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| 47. |
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| 48. |
- Holmér, Gunnel, 1955-
(författare)
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Flaskor på löpande band : Arbete och arbetskraftsrekrytering vid Surte glasbruk 1943-1978
- 2017
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation considers how the transition from craft manufacture to mechanized glass production affected the organization of work and the consequences for the recruitment of labour. Based on gender and ethnicity, the dissertation studies the composition of the workforce, the significance of qualifications, and differences in career paths and length of stay have been investigated at Surte glassworks 1943–1978. Charles Tilly’s theory of durable inequality is applied to analyse whether primarily gender and ethnicity had any effect on the assignment of tasks and on discrimination. In conclusion, the results from Surte are compared with conditions at Kosta glassworks. Whereas Surte’s specialty was machine-made bottles, Kosta was geared to craft production of utility glass and art glass.After mechanization at Surte, machine-tenders were counted among the most qualified category, instead of the glass-blowers who had previously been in demand. Manufacture at a pace regulated by machines led to more routine chores such as inspection and packaging. At Kosta, with its focus on craft, glass-blowers still had the highest positions and had learned glass-blowing in the traditional way through practical exercise. At neither Surte nor Kosta did women have any opportunity to receive comparable training.After the Second World War there was a growing need for labour at both Surte and Kosta, and to keep production going the main alternative was foreign labour. The peak was reached in the 1960s, and of roughly 660 collectively employed workers at Surte in November 1964, almost 40% were immigrants, chiefly from Finland. Kosta at the same time, with just under 330 employees, had slightly under 10% foreign workers, mainly from Greece. Kosta attracted a number of skilled glass-workers from abroad, but the majority of immigrants there, and all those at Surte, lacked experience of glass manufactureAt neither Surte nor Kosta, with their different production methods, is there any evidence of durable inequality based on ethnicity. The assignment of tasks was guided rather by the functions in demand at the companies and by the applicants’ qualifications. Internal training and career opportunities were open to all male workers, regardless of which country they came from. On the other hand, the gender division of labour at both glassworks created durable inequality for all women regardless of nationality.
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| 49. |
- Jimenez, Maria A, et al.
(författare)
-
Critical role for Ebf1 and Ebf2 in the adipogenic transcriptional cascade
- 2007
-
Ingår i: Molecular and Cellular Biology. - 0270-7306 .- 1098-5549. ; 27:2, s. 743-757
-
Tidskriftsartikel (refereegranskat)abstract
- The Ebf (O/E) family of helix-loop-helix transcription factors plays a significant role in B lymphocyte and neuronal development. The three primary members of this family, Ebf1, 2, and 3, are all expressed in adipocytes, and Ebf1 promotes adipogenesis when overexpressed in NIH 3T3 fibroblasts. Here we report that these three proteins have adipogenic potential in multiple cellular models and that peroxisome proliferator-activated receptor (PPAR) is required for this effect, at least in part due to direct activation of the PPAR1 promoter by Ebf1. Ebf1 also directly binds to and activates the C/EBP promoter, which exerts positive feedback on C/EBP expression. Despite this, C/EBP is dispensable for the adipogenic action of Ebf proteins. Ebf1 itself is induced by C/EBPß and , which bind and activate its promoter. Reduction of Ebf1 and Ebf2 proteins by specific short hairpin RNA blocks differentiation of 3T3-L1 cells, suggesting a critical role for these factors and the absence of functional redundancy between members of this family. Altogether, these data place Ebf1 within the known transcriptional cascade of adipogenesis and suggest critical roles for Ebf1 and Ebf2.
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| 50. |
- Johansson, Mikael, et al.
(författare)
-
Memory for perceived and imagined pictures : an event-related potential study
- 2002
-
Ingår i: Neuropsychologia, vol. 40, no. 7. - : Elsevier. ; 40:7, s. 986-1002
-
Konferensbidrag (refereegranskat)abstract
- Event-related potentials (ERPs) and behavioural measures were used to investigate recognition memory and source-monitoring judgements about previously perceived and imagined pictures. At study, word labels of common objects were presented. Half of these were followed by a corresponding picture and the other half by an empty frame, signalling to the participants to mentally visualise an image. At test, participants in a source-monitoring task made a three-way discrimination between new words and words corresponding to previously perceived and imagined pictures. Participants in an old/new-recognition task indicated whether test words were previously presented or not. In both tasks, correctly identified old items elicited more positive-going ERPs than correctly judged new items. This widely distributed old/new effect was found to have an earlier onset and to be of a greater magnitude for imagined than for perceived items. Task (source versus item-memory) affected the old/new effects over prefrontal areas and the reaction times to remembered old items. The present findings are consistent with the view that a greater amount, or a different type, of information is necessary for accurate source-memory judgements than for correct recognition, and moreover, that different types of source-specifying information revive at different rates. In addition, the results add weight to the view that the late widespread ERP-old/new effect is sensitive to the quality or the amount of information retrieved from memory.
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