| 1. |
- Gard, Anna, et al.
(författare)
-
Quality of life of ice hockey players after retirement due to concussions
- 2020
-
Ingår i: Concussion. - : Future Medicine. - 2056-3299. ; 5:3
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Sports-related concussion (SRC) is increasingly recognized as a potential health problem in ice hockey. Quality of life (QoL) in players retiring due to SRC has not been thoroughly addressed. Materials & methods: QoL using the Sports Concussion Assessment Tool 5th Edition, Impact of Event Scale-Revised and Short Form Health Survey was measured in Swedish ice hockey players who retired due to persistence of postconcussion symptoms or fear of attaining additional SRC. Results: A total of 76 players were assessed, on average of 5 years after their most recent SRC. Overall, retired players had a high burden of postconcussion symptoms and reduced QoL. Conclusion: Retired concussed ice hockey players have a reduced QoL, particularly those retiring due to postconcussion symptoms. Symptom burden should be continuously evaluated and guide the decision to retire.
|
|
| 2. |
- Andersson, Niklas, 1970, et al.
(författare)
-
Drug-induced prevention of gastrectomy- and ovariectomy-induced osteopaenia in the young female rat.
- 2002
-
Ingår i: The Journal of endocrinology. - : Bioscientifica. - 0022-0795 .- 1479-6805. ; 175:3, s. 695-703
-
Tidskriftsartikel (refereegranskat)abstract
- Both ovariectomy (Ovx) and gastrectomy (Gx) induce osteopaenia in rats and humans. While the effect of Ovx has been ascribed to oestrogen deficiency, the underlying mechanism behind Gx is poorly understood. Alendronate, oestrogen and parathyroid hormone (PTH) are known to prevent the osteopaenia induced by Ovx in rats. The purpose of the present study was to determine whether alendronate, oestrogen or PTH could also prevent Gx-evoked osteopaenia. Rats were Ovx-, Gx-, or were sham-operated (Sham) and were then treated with alendronate (50 micro g/kg/day), oestrogen (10 micro g/kg/day) or PTH(1-84) (75 micro g/kg/day) for eight weeks. At sacrifice, serum PTH was unaffected by surgery (Ovx, 64+/-8 pg/ml; Gx, 75+/-13 pg/ml; Sham, 58+/-11 pg/ml). The bone mineral density (BMD) of the fifth lumbar vertebra (L5) was analysed. Ovx and Gx reduced the BMD (ash weight/Volume) of the L5 by 15+/-4% and 22+/-3% respectively. Trabecular BMD and the cortical bone mineral content (BMC) of the femur were assessed using peripheral computed tomography. Both Ovx and Gx markedly reduced trabecular BMD in the metaphyseal area of the distal femur (Ovx, -37+/-7%; Gx, -49+/-7%). The cortical BMC of the femur was only slightly reduced. Alendronate prevented trabecular bone loss after both Ovx and Gx, while oestrogen and PTH prevented trabecular bone loss after Ovx but not after Gx. In conclusion, the bisphosphonate alendronate prevented both Ovx- and Gx-induced trabecular bone loss. In contrast, PTH and oestrogen prevented Ovx-induced but not Gx-induced trabecular bone loss, suggesting that the mechanism behind the trabecular bone loss in Ovx rats differs from that in Gx rats. The results support the notion that the mechanism of action for the bone-sparing effect of these drugs differs. The ability of alendronate, and probably also other bisphosphonates, to prevent Gx-evoked osteopaenia in the rat might be of potential clinical interest when dealing with post-Gx osteopaenia in humans.
|
|
| 3. |
- Andersson, Niklas, 1970, et al.
(författare)
-
Pharmacological treatment of osteopenia induced by gastrectomy or ovariectomy in young female rats.
- 2004
-
Ingår i: Acta orthopaedica Scandinavica. - : Medical Journals Sweden AB. - 0001-6470 .- 1651-1964. ; 75:2, s. 201-9
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Both gastrectomy (GX) and ovariectomy (OVX) induce osteopenia in man and experimental animals. The present study addresses the question--can alendronate, estrogen or parathyroid hormone (PTH) be used to treat established GX- or OVX -evoked osteopenia? METHODS: Rats were GX-, OVX- or SHAM-operated 8 weeks before starting the treatment with drugs. Each group was then treated for 8 weeks with 50 microg/kg/day alendronate, 10 microg/kg/day estrogen or 75 microg/kg/day PTH(1-84); n = 8 rats/group. Peripheral Quantitative Computed Tomography (pQCT) was used to measure trabecular bone mineral density (BMD) and various cortical bone parameters. RESULTS: At killing, 16 weeks after surgery, GX and OVX rats had a greatly reduced trabecular BMD in the metaphysis of the distal femur (GX -44% and OVX -55%). Alendronate increased the trabecular BMD by 44% in GX rats and by 64% in OVX rats, while PTH increased it by 51% and 115%, respectively. However, estrogen increased the trabecular BMD in GX rats (35%), but not in OVX rats (15%, not significant). Cortical bone parameters were adversely (but moderately) affected by GX, but not by OVX or by treatment with the three drugs. INTERPRETATION: Alendronate, estrogen and PTH restored the trabecular bone loss in rats with an established GX-evoked osteopenia. In contrast, alendronate and PTH, but not estrogen, restored the trabecular bone loss after OVX. Hence, the mechanism underlying GX-evoked bone loss differs from that underlying OVX-evoked bone loss. The ability of alendronate, estrogen and PTH to reverse the GX-evoked osteopenia in the rat may be of clinical interest when dealing with bone loss in humans after GX.
|
|
| 4. |
- Engström, Åsa, et al.
(författare)
-
Losing the identity of a hockey player : the long-term effects of concussions
- 2020
-
Ingår i: Concussion. - : Future Medicine. - 2056-3299. ; 5:2
-
Tidskriftsartikel (refereegranskat)abstract
- Aim: To describe what suffering multiple concussions meant for former semi-professional or professional hockey players who were forced to end their career. Results: Nine former Swedish hockey players, who once played on national or professional teams were interviewed. The interviews were analyzed with reference to hermeneutic phenomenology to interpret and explain their experiences. The theme of losing one’s identity as a hockey player was constructed from five subthemes: being limited in everyday life, returning to the hockey stadium as soon as possible, forming a post career identity, lacking understanding and support, and preventing injuries by respecting other players. Conclusion: The former hockey players struggled with developing their off-the-ice identities and with finding other sources of meaning for their lives.Lay abstractDespite considerable attention to improving the initial management of concussions suffered by hockey players, few studies have examined their long-term effects. In response, the study reported here aimed to describe what suffering multiple concussions meant for former semi-professional or professional hockey players who were forced to end their career. Nine former Swedish hockey players, who once played on national or professional teams were interviewed and the interviews were analyzed in order to interpret and explain their experiences. The overall theme was formulated as losing one’s identity as a hockey player. In conclusion, the former hockey players seem to struggle with developing their off-the-ice identities and with finding other sources of meaning for their lives.
|
|
| 5. |
- Frisk, U., et al.
(författare)
-
The Odin satellite - I. Radiometer design and test
- 2003
-
Ingår i: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 402:3, s. L27-L34
-
Tidskriftsartikel (refereegranskat)abstract
- The Sub-millimetre and Millimetre Radiometer (SMR) is the main instrument on the Swedish, Canadian, Finnish and French spacecraft Odin. It consists of a 1.1 metre diameter telescope with four tuneable heterodyne receivers covering the ranges 486-504 GHz and 541-581 GHz, and one fixed at 118.75 GHz together with backends that provide spectral resolution from 150 kHz to 1 MHz. This Letter describes the Odin radiometer, its operation and performance with the data processing and calibration described in Paper II.
|
|
| 6. |
- Kruse, Johan, et al.
(författare)
-
Scrutinized with inadequate control and support : Interns' experiences communicating with and writing referrals to hospital radiology departments - A qualitative study
- 2016
-
Ingår i: Radiography. - : Elsevier BV. - 1078-8174 .- 1532-2831. ; 22:4, s. 313-318
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: Interns' experiences communicating with and writing referrals to hospital radiology departments are important for patient safety, image quality, and decision-making in the diagnostic process. Understanding roles within the department and in the diagnostic process is important for communication. This study aimed to describe interns' experiences communicating with and writing referrals to their hospital's radiology department. Method: A qualitative study design was used. Data was collected from focus discussions with ten interns in three focus groups in Northern Sweden during 2012. The data were subjected to qualitative content analysis. Results: One theme, "a feeling of being scrutinized and lacking control", was identified in the final categories. The interns experienced that the radiology department placed high demands on them and desired more diagnostic skills training, resources and feedback. The interns suggested the following improvements: enhanced dialogue and feedback, improved education, handy guidelines, and practice writing referrals. Conclusion: Interns need more feedback from, and dialogue with, members of the Department of Radiology. They also need more knowledge of referral guidelines, appropriateness criteria and more practice to develop their knowledge and skill for writing referrals. They describe feelings of inadequate support and feel scrutinized in demanding work conditions and need more collaboration. They also need more time and more control of radiology outcomes, and they are eager to learn.
|
|
| 7. |
|
|
| 8. |
- Lehto, Niklas
(författare)
-
Dislocations in silicon
- 1998
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The topic of this thesis is theoretical studies of the electrical and structural properties in the elemental semiconductor silicon. Because of the numerous and powerful applications of semiconductors, e.g., rectifiers, transistors, solar cells and lasers, they have been the focus of huge amounts of research. Electronic devices necessitate use of almost pure semiconductor materials, normally in the form of a single crystal. In this crystal an accurately measured amount, usually extremely small, of a foreign dopant has been included to control its electrical properties. The properties of a device may be distributed by unwanted defects. Dislocations are examples of defects that degrade the performance of an electronic device, and they may even cause breakdown. This is due to the influence of dislocations on density, mobility and, most importantly, lifetime of the electrical carriers in the material. In newer semiconductor materials, such as III-V compounds, Si-Ge alloys, heterostructures and strained layers, dislocations cause problems. Dislocations in silicon are amenable more than most other solids to many different characterisation techniques and theoretical approaches. Therefore, a thorough understanding of dislocations in silicon is valuable, and an important milestone in the longer journey towards a comprehensive description of dislocations in all semiconductors. This thesis presents theoretical calculations focused on dislocations and some dislocation-related defects in silicon. Firstly, the electronic states of intrinsic stacking faults bounded by dislocations are investigated. Such stacking faults are one constituent part of commonly occurring extended dislocations in silicon. Secondly, the electronic and atomic structure of vacancies interacting with dislocations is investigated. This is important since vacancies are gettered by dislocations. Finally dislocation- dislocation interaction and its effects on the core structure of the so- called 90* partial dislocation are investigated. In order to study dislocation-dislocation interactions, a new and self-constitent method to apply periodic boundary conditions is introduced.
|
|
| 9. |
- Lehto, Niklas
(författare)
-
Effects of age on marathon finishing time among male amateur runners in Stockholm marathon 1979-2014
- 2016
-
Ingår i: Journal of Sport and Health Science. - : Elsevier BV. - 2095-2546 .- 2213-2961. ; 5:3, s. 349-354
-
Tidskriftsartikel (refereegranskat)abstract
- PurposeThe purpose of the present study was to investigate the age-related changes in the endurance performance among male amateur marathon runners.MethodsSubjects were taken from the 36 Stockholm Marathons heldfrom 1979 through 2014, and age and finishing time were analyzed for a total of 312,342male runners.ResultsThe relation was found to be a second-order polynomial, t = a + bx + cx2, which models 99.7% of the variation in the average running time t as a function of age x. The model shows that the marathon performance of the average runner improves up to age 34.3 ± 2.6 years, thereafter, the performance starts to decline. Aquantification of the age’s influence on running time shows that it accounts for 4.5% of the total variance seen in the performance data.ConclusionThese outcomes indicate that the effect of age on performance in endurance running events is clearly measurable, quantifiable and possible to describe. At the same time the findings indicate that other factors, such as training, affect the performance more. A comparison with the elite showed peak performance at the same age, but the rates of change in performance with age, improvement as well as degradation, was found to be higher among the elite.
|
|
| 10. |
- Lehto, Niklas, et al.
(författare)
-
Effects of dislocation interactions : application to the period-doubled core of the 90° partial in silicon
- 1998
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 80:25, s. 5568-5571
-
Tidskriftsartikel (refereegranskat)abstract
- The elastic strain field of a dislocation is highly affected by nearby dislocations. The effects of dislocation-dislocation interactions on elastic energy and core structure are analyzed using a new and self-consistent method to apply periodic boundary conditions on unit cells containing dislocations. Local density functional theory on hydrogen terminated clusters is used to gauge the effects of long-range elastic fields on the core structure of the 90° partial in silicon. It is shown that the single and double period structures of this core are very close in energy, and that the structure adopted probably depends on the environment in which the dislocation is located
|
|
