| 1. |
- Andersson, Helena M, et al.
(författare)
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Elite football on artificial turf versus natural grass : movement patterns, technical standards, and player impressions
- 2008
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Ingår i: Journal of Sports Sciences. - : Informa UK Limited. - 0264-0414 .- 1466-447X. ; 26:2, s. 113-22
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to examine the movement patterns, ball skills, and the impressions of Swedish elite football players during competitive games on artificial turf and natural grass. Time - motion analyses (36 observations) and technical analyses (16 team observations) were performed and 72 male and 21 female players completed a questionnaire. No differences were observed between artificial turf and natural grass in terms of total distance covered (mean 10.19 km, s = 0.19 vs. 10.33 km, s = 0.23), high-intensity running (1.86 km, s = 0.10 vs. 1.87 km, s = 0.14), number of sprints (21, s = 1 vs. 22, s = 2), standing tackles (10, s = 1 vs. 11, s = 1) or headers per game (8, s = 1 vs. 8, s = 1), whereas there were fewer sliding tackles (P < 0.05) on artificial turf than natural grass (2.1, s = 0.5 vs. 4.3, s = 0.6). There were more short passes (218, s = 14 vs. 167, s = 12) and midfield-to-midfield passes (148, s = 11 vs. 107, s = 8) (both P < 0.05) on artificial turf than natural grass. On a scale of 0-10, where 0 = "better than", 5 = "equal to", and 10 = "worse than", the male players reported a negative overall impression (8.3, s = 0.2), poorer ball control (7.3, s = 0.3), and greater physical effort (7.2, s = 0.2) on artificial turf than natural grass. In conclusion, the running activities and technical standard were similar during games on artificial turf and natural grass. However, fewer sliding tackles and more short passes were performed during games on artificial turf. The observed change in playing style could partly explain the male players' negative impression of artificial turf.
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| 2. |
- Agardh, Carl-David, et al.
(författare)
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Lack of association between plasma homocysteine levels and microangiopathy in type 1 diabetes mellitus
- 1994
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Ingår i: Scandinavian Journal of Clinical & Laboratory Investigation. - : Informa UK Limited. - 1502-7686 .- 0036-5513. ; 54:8, s. 637-641
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Tidskriftsartikel (refereegranskat)abstract
- The reactive vascular-injuring amino acid homocysteine was previously shown to be increased in plasma in diabetic patients with clinical signs of nephropathy. In this study, plasma homocysteine was measured in type 1 diabetic patients with normoalbuminuria (n = 22), microalbuminuria (n = 40) and proteinuria (n = 14) in order to investigate whether plasma homocysteine levels are increased already at the stage of incipient nephropathy, i.e. microalbuminuria. Furthermore, patients were characterized according to the degree of retinopathy. Plasma homocysteine in the whole population (n = 76) was related to B-Folate (r = 0.38, p < 0.01), S-Creatinine (r = 0.55, p < 0.001), S-Urea (r = 0.37, p < 0.01), U-Albumin (r = 0.46, p < 0.001), urinary N-acetyl-beta- glucosaminidase (r = 0.40, p < 0.001), systolic blood pressure (r = 0.36, p < 0.01) and diabetes duration (r = 0.44, p < 0.001). There were no differences in plasma homocysteine levels between patients with normoalbuminuria (8.0 +/- 1.7 mumol l-1; mean +/- SD) and those with microalbuminuria (9.1 +/- 3.4 mumol l-1). However, patients with clinical signs of nephropathy had higher plasma homocysteine levels (12.9 +/- 5.7 mumol l-1, p < 0.01) compared to the other two groups. There was no association between plasma homocysteine levels and different degrees of retinopathy. Thus, the present study does not show any relation between plasma homocysteine levels and early stages of diabetic nephropathy or retinopathy indicating that elevated concentrations of plasma homocysteine does not explain the increased risk for atherosclerosis observed in patients with microalbuminuria.
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| 3. |
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| 4. |
- Andersson, Björn A., 1968
(författare)
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Material Constraints on Technology Evolution: The Case of Scarce Metals and Emerging Energy Technologies
- 2001
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A radical transformation of the energy system in the 21st century will require a large-scale diffusion of a range of new energy technologies. Thin-film solar photovoltaics (PV) and battery-electric vehicles have been suggested as possible major components of a more sustainable energy system. However, some PV and battery designs that are promising in the short term may be constrained in the long term by their requirement for rare metals. Such constraints can materialise in the form of resource scarcity or detrimental environmental effects. Critical factors that determine metal availability and requirement are identified and quantitatively assessed for four thin-film PV designs and nine batteries. The assessment comprises the elements cadmium, cobalt, gallium, germanium, indium, lead, lithium, nickel, rare-earth elements, ruthenium, selenium, tellurium and vanadium. The technology potentials in terms of calculated material-constrained stocks and growth rates are considerably above current stocks and production levels, but, for many of the technologies, well below the scale of envisioned long-term demand. Technologies that are promising in the short to medium term but constrained in the long term may function as bridging technologies that pave the way for technologies that are sustainable on the large scale, or as dead-end technologies that lock them out. The outcome is dependent on how the technology moulds the selection environment through a number of lock-in mechanisms. Eight areas are identified, that need to be addressed by policy and far-sighted strategy to increase technology potentials and to form sustainable technological trajectories: (1) efficient materials use, (2) waste mining and stockpiling of rare metals, (3) coordinated policies to escape carbon lock-in, (4) high environmental standards for emerging technologies, (5) continued search for new technologies based on abundant elements, (6) balance between the requirements of cost reductions and sustained technological variety, (7) adjustment of technology expectations to long-term constraints, and (8) repeated monitoring of the process of technical choice and its long-term consequences.
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| 5. |
- Andersson, Björn A., 1968, et al.
(författare)
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Materials constraints in a global energy scenario based on thin-film solar cells
- 1998
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Ingår i: Energy. - 0360-5442 .- 1873-6785. ; 23, s. 407-411
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Tidskriftsartikel (refereegranskat)abstract
- Harnessing solar energy by using photovoltaic cells has the potential to become a major CO2-free energy source. Materials requirements for the solar cells based on four types of thin-film photovoltaics have been estimated and compared with global reserves, resources and annual refining. The use of solar cells based on Cd, Ga, Ge, In, Ru, Se and Te as a major energy-supply technology has severe resource constraints. Other systems such as a-Si without Ge and crystalline silicon do not involve such constraints. For some of these metals, there is the risk of enhanced, environmentally deleterious concentrations in the ecosphere due to leakage from manufacturing, use or waste handling.
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| 6. |
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| 7. |
- Andersson, Björn A., 1968, et al.
(författare)
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Monitoring and assessing technology choice: the case of solar cells
- 2000
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Ingår i: Energy Policy. ; 28, s. 1037-1049
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this paper is to suggest a methodology that will help us to determine if the present rate and direction of technological change is compatible with the development of a sustainable society. We combine two perspectives on technology assessment. The first focuses on current techno-economic trends and the second on long-term resource and environmental constraints to the diffusion of a new technology. We apply our approach to the case of solar cells. Based on an analysis of technology, actor and market dynamics we suggest that thin-film solar cells are about to dominate the industry. Within the thin-film family, there is competition between alternative designs. The diffusion of three of these will, however, be limited by resource, and perhaps emission, constraints. One design (a-Si) fares much better in terms of these constraints but is less efficient. Three policy issues are identified. First, the diffusion of solar cells is not yet self-sustained and further policy intervention is required. Second, the problems of the current thin-film designs suggest that there is a need for policies both to sustain variety and to balance that requirement with the short-term requirement of cost reduction. Third, policy must ensure that a diffusion of solar cells containing scarce metals does not lead to an erosion of environmental constraints.
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| 8. |
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| 9. |
- Andersson, Eva A, et al.
(författare)
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Improving Strength, Power, Muscle Aerobic Capacity, and Glucose Tolerance through Short-term Progressive Strength Training Among Elderly People.
- 2017
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Ingår i: Journal of Visualized Experiments. - : MyJove Corporation. - 1940-087X. ; :125
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Tidskriftsartikel (refereegranskat)abstract
- This protocol describes the simultaneous use of a broad span of methods to examine muscle aerobic capacity, glucose tolerance, strength, and power in elderly people performing short-term resistance training (RET). Supervised progressive resistance training for 1 h three times a week over 8 weeks was performed by RET participants (71±1 years, range 65-80). Compared to a control group without training, the RET showed improvements on the measures used to indicate strength, power, glucose tolerance, and several parameters of muscle aerobic capacity. Strength training was performed in a gym with only robust fitness equipment. An isokinetic dynamometer for knee extensor strength permitted the measurement of concentric, eccentric, and static strength, which increased for the RET group (8-12% post- versus pre-test). The power (rate of force development, RFD) at the initial 0-30 ms also showed an increase for the RET group (52%). A glucose tolerance test with frequent blood glucose measurements showed improvements only for the RET group in terms of blood glucose values after 2 h (14%) and the area under the curve (21%). The blood lipid profile also improved (8%). From muscle biopsy samples prepared using histochemistry, the amount of fiber type IIa increased, and a trend towards a decrease in IIx in the RET group reflected a change to a more oxidative profile in terms of fiber composition. Western blot (to determine the protein content related to the signaling for muscle protein synthesis) showed a rise of 69% in both Akt and mTOR in the RET group; this also showed an increase in mitochondrial proteins for OXPHOS complex II and citrate synthase (both ~30%) and for complex IV (90%), in only the RET group. We demonstrate that this type of progressive resistance training offers various improvements (e.g., strength, power, aerobic capacity, glucose tolerance, and plasma lipid profile).
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