| 1. |
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| 2. |
- Carlsson, Magnus, et al.
(författare)
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Gross and delta efficiencies during uphill running and cycling among elite triathletes.
- 2020
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 120:5, s. 961-968
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To investigate the gross efficiency (GE) and delta efficiency (DE) during cycling and running in elite triathletes.METHODS: Five male and five female elite triathletes completed two incremental treadmill tests with an inclination of 2.5° to determine their GE and DE during cycling and running. The speed increments between the 5-min stages were 2.4 and 0.6 km h-1 during the cycling and running tests, respectively. For each test, GE was calculated as the ratio between the mechanical work rate (MWR) and the metabolic rate (MR) at an intensity corresponding to a net increase in blood-lactate concentration of 1 mmol l-1. DE was calculated by dividing the delta increase in MWR by the delta increase in MR for each test. Pearson correlations and paired-sample t tests were used to investigate the relationships and differences, respectively.RESULTS: There was a correlation between GEcycle and GErun (r = 0.66; P = 0.038; R2 = 0.44), but the correlation between DEcycle and DErun was not statistically significant (r = - 0.045; P = 0.90; R2 = 0.0020). There were differences between GEcycle and GErun (t = 80.8; P < 0.001) as well as between DEcycle and DErun (t = 27.8; P < 0.001).CONCLUSIONS: Elite triathletes with high GE during running also have high GE during cycling, when exercising at a treadmill inclination of 2.5°. For a moderate uphill incline, elite triathletes are more energy efficient during cycling than during running, independent of work rate.
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| 3. |
- Carlsson, Magnus, et al.
(författare)
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Oxygen uptake at different intensities and sub-techniques predicts sprint performance in elite male cross-country skiers
- 2014
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Ingår i: European Journal of Applied Physiology. - : Springer. - 1439-6319 .- 1439-6327. ; 114:12, s. 2587-2595
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To investigate the relationship between sprint-prologue performance (using the classical technique) and the oxygen uptake at the lactate threshold (V̇O2obla), maximal oxygen uptake (V̇O2max), and mean oxygen uptake during double poling (V̇O2dp).METHODS: Eight elite male cross-country skiers [age 24.8 ± 4.8 years, (mean ± SD)] completed two treadmill roller-skiing tests using the diagonal-stride technique and a 60 s double-poling test on a ski-ergometer to determine their V̇O2obla, V̇O2max, and V̇O2dp. Performance data were generated from a 1.25 km sprint prologue. Power-function modelling was used to predict the skiers' race speeds based on the oxygen-uptake variables and body mass.RESULTS: There were correlations between the race speed and the absolute expression of the V̇O2obla (r = 0.79, P = 0.021), V̇O2max (r = 0.86, P = 0.0069), and V̇O2dp (r = 0.94, P = 0.00062). The following power-function models were established for race-speed prediction: 1.09 · V̇O2obla(0.21), 1.05 · V̇O2max(0.21), and 1.19 · V̇O2dp(0.20); these models explained 60 % (P = 0.024), 73 % (P = 0.0073), and 87 % (P = 0.00073), respectively, of the variance in the race speed. However, body mass did not contribute to any of the models (P = 0.97, 0.88, and 0.21, respectively).CONCLUSIONS: Oxygen uptake at different intensities and sub-techniques is an indicator of elite male sprint-prologue performance. The absolute expression of the investigated oxygen-uptake variables should be used when evaluating elite male sprint-prologue performances; if skiers oxygen uptake differs by 1 %, their performances will likely differ by 0.2 % in favour of the skier with higher oxygen uptake.
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| 4. |
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| 5. |
- Arnell, Magnus, et al.
(författare)
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Modellering av avloppsreningsverk för multikriteriebedömning av prestanda och miljöpåverkan
- 2017
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Genom att använda detaljerade dynamiska modeller och kombinera resultat från årslånga simuleringar av ARV (såväl vatten- som slamlinjer) med livscykelanalys kan olika driftstrategier utvecklas och utvärderas utifrån en bred uppsättning hållbarhetskriterier fö att maximera resursutvinning och energieffektivitet samtidigt som vattenkvalitén bibehålls och driftskostnaderna kontrolleras. Metodiken har tillämpats vid en omfattande fallstudie av Käppalaverket.
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| 6. |
- Brorsson, Sofia, et al.
(författare)
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A new electronic grip force measurement device for hand evaluation
- 2013
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Ingår i: Abstracts of the Annual European Congress of Rheumatology EULAR. June 12-15, 2013. Madrid, Spain.
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Konferensbidrag (refereegranskat)abstract
- Background: Hand grip force is a good indicator of general muscle strength and can also be used to predict multiple outcomes such as changes in activities of daily living (ADL), disability, mortality and general upper extremity strength. Hand grip force is often measured as the amount of static grip force a subject can produce when measured with a hydraulic dynamometer such as the Jamar or with an electronic device such as the Grippit. The Grippit device measures an average grip force, a peak grip force and force over a set time period. Grippit has shown good reliability for healthy subjects. Grippit, which was developed over 20 years ago in Gothenburg, Sweden is no longer manufactured. Therefore, the need for anewly developed and modernized measurement instrument for use in evaluating hand rehabilitation has arisen. Objectives: The aim of this study was to evaluate the test-retest reliability of the newly developed instrument GRIP-it and to describe and validate the relationship between grip force measurements from GRIP-it and the original Grippit device. Methods: Healthy controls (n=43) were included in the study. Two devices were used to evaluate grip force (Newton, N), (i) GRIP-it a newly developed device and (ii) Grippit. Both instruments were used to measure mean and maximal force over 10 seconds. Results: GRIP-it displayed a mean measurement error of -1.7 ± 0.5% and the corresponding error for Grippit was -1.6 ± 1.9%. All subjects completed the grip force tests and the results for three attempts for each hand. The test-retest reliability was excellent for both pieces of equipment, with ICCs ranging from 0.963 to 0.947 (CI 95% between 0.103 and 0.041) for GRIP-it and from 0.979 to 0.968 (CI 95% between 0.087 and 0.042) for Grippit. Relationships between Grippit and GRIP-itThere was a significant difference between the measured values derived from Grippit and GRIP-it for both the dominant hand (P < 0.001) and the non-dominant hand (P < 0.01). Grippit gives in general a higher grip force measurement than GRIP-it which is also indicated by the slope (β1) of the regression lines that deviates from 1. However, there were no substantial differences in the grip force when comparing the measurements for the dominant hand with the non-dominant hand for either Grippit (P = 0.071) or GRIP-it (P = 0.404). Based on these non-significant differences between hands and the fact that the model estimates for the intercept (β0) and the slope (β1) are contained within the confidence intervals of the model estimates for the opposite hand, a combined model was derived. The linear regression analysis, with grip force measurements for both hands included, gives: GRIP-it = 49.0 + 0.779 · Grippit. This explains 89.6% of the variance in grip force analyzed by GRIP-it (P < 0.001) see Figure 2. To enable an estimation of grip force measured by Grippit based on GRIP-it values a regression analysis with Grippit as dependent variable gives: Grippit = -18.1 + 1.15 · GRIP-it, which explains 89.6% of the variance in grip force analyzed by Grippit (P < 0.001).Conclusions: This study showed that GRIP-it has excellent test-retest reliability. Measurements of grip force with GRIP-it are strongly related to those from the original Grippit. The newly developed GRIP-it shows great potential for use in the assessment of hand function and the evaluation of hand rehabilitation.
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| 7. |
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| 8. |
- Carlsson, Magnus, et al.
(författare)
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Physiological demands of competitive sprint and distance performance in elite female cross-country skiing
- 2016
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Ingår i: Journal of Strength and Conditioning Research. - : Lippincott Williams & Wilkins. - 1064-8011 .- 1533-4287. ; 30:8, s. 2138-2144
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Tidskriftsartikel (refereegranskat)abstract
- The purpose was to investigate the relationship between elite females' competitive performance capability in sprint and distance cross-country skiing and the variables of gross efficiency (GE), work rate at the onset of blood-lactate accumulation (OBLA4mmol), maximal oxygen uptake (V[Combining Dot Above]O2max), maximal speed (Vmax), and peak upper-body oxygen uptake (V[Combining Dot Above]O2peak). Ten elite female cross-country skiers (age 24.5 ± 2.8 years) completed treadmill roller-skiing tests to determine GE, OBLA4mmol, and V[Combining Dot Above]O2max using the diagonal-stride technique as well as Vmax and V[Combining Dot Above]O2peak using the double-poling technique. International Ski Federations ranking points for sprint (FISsprint) and distance (FISdist) races were used as competitive performance data. There were correlations between the FISsprint and the V[Combining Dot Above]O2max expressed absolutely (p = 0.0040), Vmax (p = 0.012), and V[Combining Dot Above]O2peak expressed absolutely (p < 0.001) and as a simple ratio-standard (p = 0.049). The FISdist were correlated with OBLA4mmol (p = 0.048), V[Combining Dot Above]O2max expressed absolutely (L·min) (p = 0.015) and as a simple ratio-standard (p = 0.046), and V[Combining Dot Above]O2peak expressed absolutely (p = 0.036) and as a simple ratio-standard (ml·min·kg) (p = 0.040). The results demonstrate that the physiological abilities reflected by V[Combining Dot Above]O2max and V[Combining Dot Above]O2peak are indicators of competitive sprint and distance performance in elite female cross-country skiing. In addition, the ability to generate a high Vmax indicates the performance in sprint races, whereas the skier's OBLA4mmol reflects the performance capability in distance races. Based on the results, when evaluating the performance capacity of elite female cross-country skiers, it is recommended to use physiological variables that reflect competitive performance.
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| 9. |
- Carlsson, Magnus, et al.
(författare)
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Prediction of race performance of elite cross-country skiers by lean mass
- 2014
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Ingår i: International Journal of Sports Physiology and Performance. - : Human Kinetics. - 1555-0265 .- 1555-0273. ; 9:6, s. 1040-1045
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To investigate the relationship between race performance and lean mass (LM) variables, as well as to examine sex differences in body composition in elite-standard cross-country skiers. Methods: Thirty-four elite cross-country skiers (18 men and 16 women) underwent a dual-emission x-ray absorptiometry body composition test to determine LM, fat mass, and bone mineral content. For both sexes, performance data were collected from a sprint prologue and a distance race. Results: The absolute expression of LM variables [whole body (LMWB), upper body (LMUB), and lower body (LMLB)] was significantly correlated with finishing time in the sprint prologue independent of sex. Distance-race performance was significantly related to LMWB, LMUB, and LMLB in women; however, no correlation was found in men. Men had a significantly higher LM and lower fat mass, independent of expression (absolute or relative), for the whole body, arms, trunk, and legs, except for the absolute fat mass in the trunk. Conclusions: The absolute expressions of LMWB, LMUB, and LMLB were significant predictors of sprint-prologue performance in both sexes, as well as of distance-race performance in women only. Compared with women, male skiers have a higher LM in the body segments that are major contributors to propelling forces. These results suggest that muscle mass in the lower and upper body is equally important for race performance; thus, more focus of elite skiers’ training should be directed to increasing whole-body muscle mass to improve their competitive performance capability.
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| 10. |
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| 11. |
- Carlsson, Magnus, et al.
(författare)
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The acute effects of a short technique-intense training period on side-foot kick performance among elite female soccer players
- 2019
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Ingår i: Journal of Sports Medicine and Physical Fitness. - 0022-4707 .- 1827-1928. ; 59:9, s. 1442-1449
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Previously, it was shown that elite soccer teams were 24% more likely to win matches if their passing effectiveness were increased by 1%. However, research interventions aiming to improve passing performance are scarce. The current study aimed to investigate the effect of a short technique-intense training period on side-foot kick performance among elite female soccer players.METHODS: Four side-foot kick tests were completed before and after a training period: kicking a stationary ball using match-relevant (SBRS) and maximal ball speed (SBMS), passing the ball on the move using match-relevant ball speed (RBRS), and repeated side-foot kicks onto a rebound-box with continuously increasing passing distance (RRB). The players were assigned to either the intervention group or the control group. The training intervention consisted of six 55-min training sessions with five side-foot kick exercises. Within-group and between-group differences were investigated using paired-samples t-test and Mann-Whitney U test, respectively.RESULTS: The intervention group improved the performance in the RBRS and RRB tests (both P < 0.05), but no differences were found for the SBRS and SBMS tests (both P > 0.05). No improvements were found for the control group independent of test condition (all P > 0.05). Significant between-group differences were found for the RBRS and RRB tests (both P < 0.05), whereas no differences were found for the SBRS and SBMS tests (both P > 0.05).CONCLUSIONS: The fundamental soccer skill of passing a moving ball was improved in elite female soccer players by a short technique-intense training period.
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| 12. |
- Carlsson, Magnus, et al.
(författare)
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The effect of ball temperature on ball speed and carry distance in golf drives
- 2018
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Ingår i: Proceedings of the Institution of Mechanical Engineers, Part P. - London, UK : Sage Publications. - 1754-3371. ; 233:2, s. 186-192
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to investigate the effect of ball temperature on impact ball speed and carry distance during golf drives in a blind randomized test design. The balls were exposed to a temperature-controlled environment (4 °C, 18 °C, 32 °C, and 46 °C) for 24 h prior to the test and each temperature group consisted of 30 balls. The 120 drives were performed by an elite male golfer (handicap: 0.0) in an indoor driving range. All drives were measured by a Doppler-radar system to determine the club-head speed, launch angle, spin rate, ball speed, and carry distance. Differences between the groups were investigated using a one-way analysis of variance. The results indicated that ball-speed and carry-distance differences occurred within the four groups (p < 0.001 and p < 0.01, respectively). The post hoc analyses showed that the ball temperatures of 18 °C and 32 °C had greater ball speeds and carry distances than balls at 4 °C and 46 °C (all p < 0.05). The intervals for the between-group differences were 0.6–0.7 m s –1 and 2.9–3.9 m for ball speed and carry distance, respectively. Hence, the results showed that ball temperature influences both the ball speed and the carry distance. Based on the findings in this study, standardization of ball temperature should be factored into governing body regulation tests for golf equipment. © IMechE 2018.
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| 13. |
- Carlsson, Magnus, et al.
(författare)
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The effect of training on side foot-kick performance among swedish first league women´s soccer players
- 2018
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Konferensbidrag (refereegranskat)abstract
- THE EFFECT OF TRAINING ON SIDE FOOT-KICK PERFORMANCE AMONG SWEDISH FIRST LEAGUE WOMEN’S SOCCER PLAYERSCarlsson, M.1, Isberg, J.1, Nilsson, J.1, Carlsson, T.1 1: Dalarna University (Falun, Sweden)IntroductionA high completion rate for passes is important for success in soccer, because longer passing sequences are related to more scored goals (Hughes & Franks, 2005). In a recent study, it was found that female players had a lower pass-completion rate than male players at the highest competitive standard of European soccer, which suggests that elite female players in general do not have the same technical characteristics as elite male players (Paul S. Bradley et al., 2014). The purpose of the study was investigate the effect of a 2-week training intervention on side foot-kick performance among Swedish first league women’s soccer players. MethodsTo investigate the effect of training on side foot-kick performance, a pre-post-intervention study was implemented where four side foot-kick tests were performed before and after a 2-week training period. The side foot-kick accuracy were investigated when kicking a stationary ball using match-relevant ball speed (SBRS) and maximal ball speed (SBMS) as well as subsequent to a 5-m run with the ball from different approach angles (0°, 30°, and 60°) to a predetermined position, where passing of the ball on the move was executed using match-relevant ball speed (RBRS). The fourth test comprised repeated side-foot kicks onto a rebound-box with continuously increasing passing distance (RRB).Based on the results from the pre-tests, the players were assigned to either the intervention group (INT) or the control group (CON). The training intervention consisted of six 55-min training sessions. In each session, two rounds of five exercises focusing on improvement of side foot-kick accuracy were executed. Within-group and between-group differences were investigated using paired samples Student’s t-tests and Mann-Whitney U tests, respectively.ResultsPrior to the training intervention, there were no significant differences between the groups for any of the investigated test variables. The INT group improved RBRS (P = 0.036) and RRB (P = 0.010) during the training intervention, whereas no significant within-group changes were found for either SBRS or SBMS (both P > 0.05). No within-group differences were found for any of the test variables in the CON group (all P > 0.05). Significant between-group differences were found for RBRS (P = 0.040) and RRB (P = 0.005), whereas no differences were found for either SBRS or SBMS (both P > 0.05).ConclusionThe fundamental soccer skill of passing a moving ball could be improved in elite women players by a 2-week training period focusing on improving side foot-kick performance.ReferencesBradley PS, Carling C, Diaz AG, Hood P, Barnes C, Ade J, Boddy M, Krustrup P, Mohr M (2013) Hum Mov Sci, 32, 808-821.Hughes M, Franks I (2005) J Sports Sci, 23, 509-514.
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| 14. |
- Carlsson, Magnus, et al.
(författare)
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The influence of sex, age, and race experience on pacing profiles during the 90 km Vasaloppet ski race
- 2016
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Ingår i: Open Access Journal of Sports Medicine. - 1179-1543. ; 7, s. 11-19
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to investigate pacing-profile differences during the 90 km Vasaloppet ski race related to the categories of sex, age, and race experience. Skiing times from eight sections (S1 to S8) were analyzed. For each of the three categories, 400 pairs of skiers were matched to have a finish time within 60 seconds, the same start group, and an assignment to the same group for the other two categories. Paired-samples Student’s t-tests were used to investigate sectional pacing-profile differences between the subgroups. Results showed that males skied faster in S2 (P=0.0042), S3 (P=0.0049), S4 (P=0.010), and S1–S4 (P<0.001), whereas females skied faster in S6 (P<0.001), S7 (P<0.001), S8 (P=0.0088), and S5–S8 (P<0.001). For the age category, old subjects (40 to 59 years) skied faster than young subjects (19 to 39 years) in S3 (P=0.0029), and for the other sections, there were no differences. Experienced subjects (≥4 Vasaloppet ski race completions) skied faster in S1 (P<0.001) and S1–S4 (P=0.0054); inexperienced skiers (<4 Vasaloppet ski race completions) had a shorter mean skiing time in S5–S8 (P=0.0063). In conclusion, females had a more even pacing profile than that of males with the same finish time, start group, age, and race experience. No clear age-related pacing-profile difference was identified for the matched subgroups. Moreover, experienced skiers skied faster in the first half whereas inexperienced skiers had higher skiing speeds during the second half of the race.
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| 15. |
- Carlsson, Magnus, et al.
(författare)
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Time trials predict the competitive performance capacity of junior cross-country skiers
- 2014
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Ingår i: International Journal of Sports Physiology and Performance. - 1555-0265 .- 1555-0273. ; 9:1, s. 12-18
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: This study investigated whether there is a correlation between time-trial performance and competitive performance capacity of male and female junior cross-country skiers and sought to explain sex-specific competitive performance capacity through multiple-regression modeling.Methods: The International Ski Federation's (FIS) junior ranking points for distance (FISdist) and sprint (FISsprint) competitions were used as performance parameters. A total of 38 elite junior (age 18.5 +/- 1.0 y) cross-country skiers (24 men and 14 women) completed 3 time-trial tests: a 3-km level-running time trial (TTRun), a 2-km moderate uphill (1.2 slope) roller-skiing time trial using the double-poling technique (TTDP), and a 2-km uphill (2.8 slope) roller-skiing time trial using the diagonal-stride technique (TTDiag). The correlations were investigated using Pearson correlation analysis, and regression models were created using multiple-linear-regression analysis. Results: For men, FISsprint and FISdist were correlated with the times for TTRun, TTDP, and TTDiag (all P < .001). For women, FISsprint was correlated with the times for TTRun (P < .05), TTDP (P < .01), and TTDiag (P < .01), whereas FISdist was correlated only with the times for TTDP (P < .01) and TTDiag (P < .05). The models developed for FISdist and FISsprint explained 73.9-82.3% of the variance in the performance capacity of male junior cross-country skiers. No statistically valid regression model was found for the women.Conclusions: Running and roller-skiing time trials are useful tests for accurately predicting the performance capacity of junior cross-country skiers.
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| 16. |
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| 17. |
- Carlsson, Magnus, et al.
(författare)
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Validation of physiological tests in relation to competitive performances in elite male distance cross-country skiing
- 2012
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Ingår i: Journal of Strength and Conditioning Research. - : National Strength and Conditioning Association. - 1064-8011 .- 1533-4287. ; 26:6, s. 1496-1504
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of the present study was to establish which physiological test parameters reflects the distance performances in the Swedish National Championships in cross-country skiing (SNC) and the International Ski Federation's ranking points for distance performances (FISdist). The present study also aimed to create multiple regression models to describe skiing performance for the SNC distance races and International Ski Federation's (FIS) ranking. Twelve male, Swedish, national elite, cross-country skiers (maximal oxygen consumption [(V) over dotO(2)max] = 5.34 +/- 0.34 L.min(-1)) volunteered to participate in the study. Their results in the 2008 SNC (15 km race [SNC15] and 30 km race [SNC30]) and FISdist points were used as performance data. On the week preceding the Championship, subjects completed a test battery consisting of 7 physiological tests: isokinetic knee extension peak torque (PT), vertical jumps (VJ), lactate threshold (LT), (V) over dotO(2)max, and 3 double poling tests of different durations (DP20, DP60, and DP360). Correlations were established using Pearson's correlation analysis, and models to describe skiing performance were created using standard multiple linear regression analysis. Significant correlations were found between the performance parameters and test parameters derived from LT, (V) over dotO(2)max, and DP60 tests. No correlations with any performance parameter were found for PT, VJ, DP20, and DP360 tests. For FISdist and SNC15, the models explain 81% and 78% of the variance in performance, respectively. No statistically valid regression model was found for SNC30. The results of this study imply that the physiological demands in male elite distance cross-country skiing performances are different in different events. To adequately evaluate a skier's performance ability in distance cross-country skiing, it is necessary to use test parameters and regression models that reflect the specific performance.
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| 18. |
- Carlsson, Rickard, et al.
(författare)
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Backlash and hiring : A field experiment on agency, communion, and gender
- 2015
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Konferensbidrag (refereegranskat)abstract
- Gender stereotypes describe women as communal and men asagentic. Laboratory based research (Rudman & Glick 1999; 2001)suggests that trying to disconfirm such descriptive genderstereotypes (e.g., women self-promoting their agency), entails therisk of hiring discrimination due to violation of prescriptive genderstereotypes: a backlash. To examine whether backlash occurs whenapplying for real jobs, we conducted a field experiment. Gender,agency and communion were manipulated in the personal profile of5,562 applications sent to 3,342 job openings on the Swedish labormarket. The dependent variable was whether the applicationresulted in an invitation to a job interview or not. The results do notoffer any support for the backlash hypothesis at this stage in therecruitment process.
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| 19. |
- Carlsson, Rickard, et al.
(författare)
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Testing for backlash in hiring : A field experiment on agency, communion,and gender
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- It has been suggested that women (men) who appear agentic (communal) when applying for jobs suffer a backlash in the form of reduced chances of being hired. However, the evidence of backlash is mainly restricted to simulated hiring decisions with undergraduates as participants. To examine whether backlash occurs when men and women apply for real jobs in the labor market, we conducted a field experiment. Gender, agentic and communal traits were manipulated in the applications. Whether or not the applications resulted in a job interview invitation constituted the dependent variable. We find no evidence of backlash, suggesting that women are not punished for presenting themselves as agentic in their job applications, nor are men punished for appearing communal.
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| 20. |
- Carlsson, Rickard, et al.
(författare)
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Testing for backlash in hiring: A field experiment on agency, communion and gender.
- 2014
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Ingår i: Journal of Personnel Psychology. - : Hogrefe Publishing Group. - 2190-5150 .- 1866-5888. ; 13:4, s. 204-214
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Tidskriftsartikel (refereegranskat)abstract
- Gender stereotypes describe women as communal and men as agentic. Laboratory-based research (Rudman & Glick, 1999, 2001) suggests that trying to disconfirm such descriptive gender stereotypes (e.g., women self-promoting their agency), entails the risk of hiring discrimination due to violation of prescriptive gender stereotypes: a backlash. To examine whether backlash occurs when applying for real jobs, we conducted a field experiment. Gender, agency, and communion were manipulated in the personal profile of 5,562 applications sent to 3,342 job openings on the Swedish labor market. The dependent variable was whether the application resulted in an invitation to a job interview or not. The results do not offer any support for the backlash hypothesis at this stage in the recruitment process.
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| 21. |
- Carlsson, Tomas, et al.
(författare)
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Aerobic power and lean mass are indicators of competitive sprint performance among elite female cross-country skiers
- 2016
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Ingår i: Open Access Journal of Sports Medicine. - 1179-1543. ; 7, s. 153-160
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to establish the optimal allometric models to predict International Ski Federation’s ski-ranking points for sprint competitions (FISsprint) among elite female cross-country skiers based on maximal oxygen uptake (V̇O2max) and lean mass (LM). Ten elite female cross-country skiers (age: 24.5±2.8 years [mean ± SD]) completed a treadmill roller-skiing test to determine V̇O2max (ie, aerobic power) using the diagonal stride technique, whereas LM (ie, a surrogate indicator of anaerobic capacity) was determined by dual-emission X-ray anthropometry. The subjects’ FISsprint were used as competitive performance measures. Power function modeling was used to predict the skiers’ FISsprint based on V̇O2max, LM, and body mass. The subjects’ test and performance data were as follows: V̇O2max, 4.0±0.3 L min-1; LM, 48.9±4.4 kg; body mass, 64.0±5.2 kg; and FISsprint, 116.4±59.6 points. The following power function models were established for the prediction of FISsprint: 3.91×105 ∙ VO -6.002maxand 6.95×1010 ∙ LM-5.25; these models explained 66% (P=0.0043) and 52% (P=0.019), respectively, of the variance in the FISsprint. Body mass failed to contribute to both models; hence, the models are based on V̇O2max and LM expressed absolutely. The results demonstrate that the physiological variables that reflect aerobic power and anaerobic capacity are important indicators of competitive sprint performance among elite female skiers. To accurately indicate performance capability among elite female skiers, the presented power function models should be used. Skiers whose V̇O2max differs by 1% will differ in their FISsprint by 5.8%, whereas the corresponding 1% difference in LM is related to an FISsprint difference of 5.1%, where both differences are in favor of the skier with higher V̇O2max or LM. It is recommended that coaches use the absolute expression of these variables to monitor skiers’ performance-related training adaptations linked to changes in aerobic power and anaerobic capacity.
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| 22. |
- Carlsson, Tomas, 1969-, et al.
(författare)
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Optimal Formula V̇O 2max -to-mass ratio for performance among elite male cross-country skiers
- 2015
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Ingår i: Open Access Journal of Sports Medicine. - 1179-1543. ; 6, s. 353-360
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was 1) to validate the 0.5 body-mass exponent for maximal. oxygen uptake [Formula: see text] as the optimal predictor of performance in a 15 km classical-technique skiing competition among elite male cross-country skiers and 2) to evaluate the influence of distance covered on the body-mass exponent for [Formula: see text] among elite male skiers. Twenty-four elite male skiers (age: 21.4±3.3 years [mean ± standard deviation]) completed an incremental treadmill roller-skiing test to determine their [Formula: see text]. Performance data were collected from a 15 km classical-technique cross-country skiing competition performed on a 5 km course. Power-function modeling (ie, an allometric scaling approach) was used to establish the optimal body-mass exponent for [Formula: see text] to predict the skiing performance. The optimal power-function models were found to be [Formula: see text] and [Formula: see text], which explained 69% and 81% of the variance in skiing speed, respectively. All the variables contributed to the models. Based on the validation results, it may be recommended that [Formula: see text] divided by the square root of body mass (mL · min(-1) · kg(-0.5)) should be used when elite male skiers' performance capability in 15 km classical-technique races is evaluated. Moreover, the body-mass exponent for [Formula: see text] was demonstrated to be influenced by the distance covered, indicating that heavier skiers have a more pronounced positive pacing profile (ie, race speed gradually decreasing throughout the race) compared to that of lighter skiers.
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| 23. |
- Carlsson, Tomas, et al.
(författare)
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Optimal V. O2max-to-mass ratio for predicting 15 km performance among elite male cross-country skiers
- 2015
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Ingår i: Open Access Journal of Sports Medicine. - : Dove Medical Press. - 1179-1543. ; 6, s. 353-360
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was 1) to validate the 0.5 body-mass exponent for maximal oxygen uptake (V. O2max) as the optimal predictor of performance in a 15 km classical-technique skiing competition among elite male cross-country skiers and 2) to evaluate the influence of distance covered on the body-mass exponent for V. O2max among elite male skiers. Twenty-four elite male skiers (age: 21.4±3.3 years [mean ± standard deviation]) completed an incremental treadmill roller-skiing test to determine their V. O2max. Performance data were collected from a 15 km classicaltechnique cross-country skiing competition performed on a 5 km course. Power-function modeling (ie, an allometric scaling approach) was used to establish the optimal body-mass exponent for V . O2max to predict the skiing performance. The optimal power-function models were found to be race speed = 8.83⋅(V . O2max m-0.53) 0.66 and lap speed = 5.89⋅(V . O2max m-(0.49+0.018lap)) 0.43e0.010age, which explained 69% and 81% of the variance in skiing speed, respectively. All the variables contributed to the models. Based on the validation results, it may be recommended that V. O2max divided by the square root of body mass (mL⋅min−1 ⋅kg−0.5) should be used when elite male skiers’ performance capability in 15 km classical-technique races is evaluated. Moreover, the body-mass exponent for V . O2max was demonstrated to be influenced by the distance covered, indicating that heavier skiers have a more pronounced positive pacing profile (ie, race speed gradually decreasing throughout the race) compared to that of lighter skiers.
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| 24. |
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| 25. |
- Carlsson, Tomas, et al.
(författare)
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Scaling maximal oxygen uptake to predict performance in elite-standard men cross-country skiers
- 2013
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Ingår i: Journal of Sports Sciences. - : Routledge. - 0264-0414 .- 1466-447X. ; 31:16, s. 1753-1760
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to: 1) establish the optimal body-mass exponent for maximal oxygen uptake (O2max) to indicate performance in elite-standard men cross-country skiers; and 2) evaluate the influence of course inclination on the body-mass exponent. Twelve elite-standard men skiers completed an incremental treadmill roller-skiing test to determine O2max and performance data came from the 2008 Swedish National Championship 15-km classic-technique race. Log-transformation of power-function models was used to predict skiing speeds. The optimal models were found to be: Race speed = 7.86 · O2max · m −0.48 and Section speed = 5.96 · O2max · m −(0.38 + 0.03 · α) · e−0.003 · Δ (where m is body mass, α is the section's inclination and Δ is the altitude difference of the previous section), that explained 68% and 84% of the variance in skiing speed, respectively. A body-mass exponent of 0.48 (95% confidence interval: 0.19 to 0.77) best described O2max as an indicator of performance in elite-standard men skiers. The confidence interval did not support the use of either “1” (simple ratio-standard scaled) or “0” (absolute expression) as body-mass exponents for expressing O2max as an indicator of performance. Moreover, results suggest that course inclination increases the body-mass exponent for O2max.
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| 26. |
- Carlsson, Tomas, et al.
(författare)
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Scaling of upper-body power output to predict time-trial roller skiing performance
- 2013
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Ingår i: Journal of Sports Sciences. - : Taylor & Francis. - 0264-0414 .- 1466-447X. ; 31:6, s. 582-588
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of the present study was to establish the most appropriate allometric model to predict mean skiing speed during a double-poling roller skiing time-trial using scaling of upper-body power output. Forty-five Swedish junior cross-country skiers (27 men and 18 women) of national and international standard were examined. The skiers, who had a body mass (m) of 69.3 ± 8.0 kg (mean ± s), completed a 120-s double-poling test on a ski ergometer to determine their mean upper-body power output (W). Performance data were subsequently obtained from a 2-km time-trial, using the double-poling technique, to establish mean roller skiing speed. A proportional allometric model was used to predict skiing speed. The optimal model was found to be: Skiing speed = 1.057 · W 0.556 · m −0.315, which explained 58.8% of the variance in mean skiing speed (P < 0.001). The 95% confidence intervals for the scaling factors ranged from 0.391 to 0.721 for W and from −0.626 to −0.004 for m. The results in this study suggest that allometric scaling of upper-body power output is preferable for the prediction of performance of junior cross-country skiers rather than absolute expression or simple ratio-standard scaling of upper-body power output.
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| 27. |
- Carlsson, Tomas, et al.
(författare)
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Scaling oxygen consumption to body mass in real elite cross-country skiing performances
- 2009
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Ingår i: Book of Abstracts. - 9788250204201 ; , s. 351-352
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Konferensbidrag (refereegranskat)abstract
- Introduction: Which are the main physiological differences between a successful and less successful cross-country skier? To our knowledgeno previous studies have examined a real elite cross-country ski competition. Main purpose of this study was therefore to validatecommonly used test parameters to skiing time and to International Ski Federation (FIS) overall seasonal ranking points and to createmultiple regression models to predict skiing performances.Methods: Twelve highly motivated male Swedish national elite cross-country skiers completed a test battery consisting of: isokinetic kneeextensor peak torque tests at three different velocities; three different vertical jumps tests; two-part treadmill roller skiing test determininglactate markers, maximal oxygen consumption (VO2max) and time to exhaustion; 60 and 360 s double poling tests determining meanupper-body power (DP60Pmean) (DP360Pmean) and mean oxygen consumption (DP60VO2mean) (DP360VO2mean).Performance data were collected from the Swedish National Championship (SNC) in cross-country skiing (13-17 March 2008): 15-km withindividual start in classical technique (SNC15); 30-km double pursuit with mass-start (SNC30); sprint prolog in free-style technique(SNCsprint). In addition to ski races, overall seasonal ski ranking points were collected from FIS 3rd Cross-Country Points List 2007/2008published before SNC for distance (FISdist) and sprint (FISsprint) races.Correlations between test parameters and performance data were established using Pearson´s correlation analysis. Prediction modelswere created using standard multiple linear regression analysis.Results: Time to exhaustion during the incremental treadmill roller ski test is best correlated with both SNC15 (r = -0.86, p < 0.001) andSNC30 (r = -0.81, p < 0.01). For SNC15 significant correlations were shown with VO2max both absolute and relative to body weight, lactatemarkers, DP60Pmean and DP60VO2mean. Corresponding correlations for SNC30 were: lactate markers, DP60VO2mean and percentagedecrease in mean knee extension peak torque when comparing highest and lowest velocities. Highest correlation coefficient forSNCsprint was found for DP60Pmean (r = -0.93, p < 0.05). Significant correlations for SNCsprint was also detected for DP360Pmean aswell as DP360VO2mean and jump height in squat jump.Prediction models explain 68, 91, 68, 77 and 82% of the variance in performance for SNC15, SNC30, SNCsprint, FISdist and FISsprint,respectively.Discussion: Correlations found in this study have validated several commonly used physiological tests with real elite cross-country skiingperformances. Frequently investigated test parameters like VO2max and anaerobic thresholds are of great importance for success incross-country skiing. Many recent research studies have focused on upper-body capacity and we could confirm that high mean powerproduction in double poling is necessary to be successful as elite skier in both sprint and distance races.
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| 28. |
- Carlsson, Tomas, et al.
(författare)
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The effect of ball temperature on ball speed and carry distance in golf drives
- 2018
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Konferensbidrag (refereegranskat)abstract
- THE EFFECT OF BALL TEMPERATURE ON BALL SPEED AND CARRY DISTANCE IN GOLF DRIVESCarlsson, T.1, Nilsson, J.1,2, Hellström, J.3, Tinmark, F.2, Carlsson, M.1. 1: Dalarna University (Falun, Sweden), 2: The Swedish School of Sport and Health Sciences (Stockholm, Sweden), 3: The Swedish Golf Federation (Stockholm, Sweden). IntroductionPreviously it was reported that golf-ball temperature has influence on the golf balls’ coefficient of restitution, impact duration, and maximal deformation (Allen et al., 2012). They concluded that their research was the first step in a process for determining the effect of temperature on a golf drive. However, how large influence the golf-ball temperature has on golf drives remains to be investigated. The purpose was to investigate the effect of ball temperature on impact ball speed and carry distance during golf drives in a blind randomized test design. MethodsThe balls were exposed to a temperature-controlled environment (4°C, 18°C, 32°C, and 46°C) for twenty-four hours prior to the test, and each of the four different ball-temperature groups consisted of 30 balls. The 120 drives were performed by an elite male golfer (handicap: 0.0) in an indoor driving range. All drives were measured by a Doppler-radar system to determine club-head speed, launch angle, spin rate, ball speed, and carry distance. Differences between the four ball-temperature groups were investigate using a one-way analysis of variance. ResultsThe results indicate that there are ball-speed and carry-distance differences within the four ball-temperature groups (P < 0.001 and P < 0.01, respectively). The post-hoc analyses showed that the ball temperatures 18°C and 32°C had both greater ball speeds and carry distances compared to the balls in the ball-temperature groups 4°C and 46°C (all P < 0.05); the intervals for the between-group differences were 2.0 to 2.4 km/h and 2.9 to 3.9 m for ball speed and carry distance, respectively.ConclusionThe novel results of the current study show that the ball’s temperature has a significant effect on the ball speed after club-head impact and carry distance for drives performed by an elite golfer. The ball temperatures 18°C and 32°C gave significantly increased ball speeds and carry distances compared to the ball-temperature groups 4°C and 46°C. This knowledge could be used to maximise the carry distance and/or to minimise the carry-distance variability related to ball temperature.REFERENCES:Allen T, Bowley A, Wood P, Henrikson E, Morales E, James D. (2012) Procedia Eng, 34, 634-639.
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| 29. |
- Carlsson, Tomas, et al.
(författare)
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The effects of strength training versus ski-ergometer training on double-poling capacity of elite junior cross-country skiers
- 2017
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 117:8, s. 1523-1532
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Tidskriftsartikel (refereegranskat)abstract
- PurposeTo compare the effects of strength training versus ski-ergometer training on double-poling gross efficiency (GE), maximal speed (Vmax), peak oxygen uptake (V˙O2peak" role="presentation" style="box-sizing: border-box; display: inline-table; line-height: normal; letter-spacing: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">V˙O2peakV˙O2peak) for elite male and female junior cross-country skiers.MethodsThirty-three elite junior cross-country skiers completed a 6-week training-intervention period with two additional 40-min training sessions per week. The participants were matched in pairs and within each pair randomly assigned to either a strength-training group (STR) or a ski-ergometer-training group (ERG). Before and after the intervention, the participants completed three treadmill roller-skiing tests to determine GE, Vmax, and V˙O2peak" role="presentation" style="box-sizing: border-box; display: inline-table; line-height: normal; letter-spacing: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">V˙O2peakV˙O2peak. Mixed between-within subjects analysis of variance (ANOVA) was conducted to evaluate differences between and within groups. Paired samples t tests were used as post hoc tests to investigate within-group differences.ResultsBoth groups improved their Vmax and V˙O2peak" role="presentation" style="box-sizing: border-box; display: inline-table; line-height: normal; letter-spacing: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">V˙O2peakV˙O2peak expressed absolutely (all P < 0.01). For the gender-specific sub-groups, it was found that the female skiers in both groups improved both Vmax and V˙O2peak" role="presentation" style="box-sizing: border-box; display: inline-table; line-height: normal; letter-spacing: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">V˙O2peakV˙O2peak expressed absolutely (all P < 0.05), whereas the only within-group differences found for the men were improvements of Vmax in the STR group. No between-group differences were found for any of the investigated variables.ConclusionsPhysiological and performance-related variables of importance for skiers were improved for both training regimes. The results demonstrate that the female skiers’ physiological adaptations to training, in general, were greater than those of the men. The magnitude of the physiological adaptations was similar for both training regimes.
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| 30. |
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| 31. |
- Carlsson, Tomas, et al.
(författare)
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The importance of scaling VO2MAX to predict cross-country skiing performance
- 2013
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Konferensbidrag (refereegranskat)abstract
- Introduction A high maximal oxygen uptake (VO2max) is of importance for success in elite male competitive distance cross-country skiing (Carlsson et al. 2012). However, it is still debatable how VO2max should be expressed to best indicate skiing performance. Therefore, the purpose of this study was to establish the optimal body mass exponent for VO2max to indicate performance in elite-standard male cross-country skiers. Methods Twenty-four elite-standard male cross-country skiers completed an incremental treadmill roller skiing test in diagonal stride technique determining VO2max. Performance data was compiled from a 15-km classic technique race. To predict performance a log-transformation of power-function model: Race speed = β0 • VO2max^β1 • m^β2 was used, where β0 to β2 are constants, and m is body mass. Statistical analyses used R version 2.13.2 (R Development Core Team, New Zeeland) and alpha was 0.05. Results Participants’ VO2max was 5.39 ± 0.57 l/min (mean ± s) and m was 75.5 ± 6.3 kg. Mean race speed was 5.83 ± 0.41 m/s. The model that best predicted performance was: Race speed = 8.829 • VO2max^0.663 • m^-0.355 = 8.829 • (VO2max • m^–0.535 )^0.663, that explains 69.2% of the variance in race speed for the 15-km classic technique race (P < 0.001). For the VO2max-to-mass ratio within the model, the 95% confidence interval (CI) for the body-mass exponent ranged from -0.947 to -0.122. Discussion The optimal body mass exponent for VO2max to indicate performance in elite-standard male cross-country skiers was -0.535. Moreover, the CI for the body-mass exponent does not support the use of simple ratio-standard scaling and absolute expression of VO2max as indicators of 15 km classic ski racing performance in elite-standard men skiers.
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| 32. |
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| 33. |
- Carlsson, Tomas, et al.
(författare)
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The Modern Double-Poling Technique Is Not More Energy Efficient Than the Old-Fashioned Double-Poling Technique at a Submaximal Work Intensity
- 2022
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Ingår i: Frontiers in Sports and Active Living. - : Frontiers Media SA. - 2624-9367. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of the study was to investigate whether there are energy-efficiency differences between the execution of the old-fashioned double-poling technique (DPOLD) and the modern double-poling technique (DPMOD) at a submaximal work intensity among elite male cross-country skiers. Fifteen elite male cross-country skiers completed two 4-min tests at a constant mechanical work rate (MWR) using the DPMOD and DPOLD. During the last minute of each test, the mean oxygen uptake (VO2) and respiratory exchange ratio (RER) were analyzed, from which the metabolic rate (MR) and gross efficiency (GE) were calculated. In addition, the difference between pretest and posttest blood-lactate concentrations (BLadiff) was determined. For each technique, skiers’ joint angles (i.e., heel, ankle, knee, hip, shoulder, and elbow) were analyzed at the highest and lowest positions during the double-poling cycle. Paired-samples t-tests were used to investigate differences between DPMOD and DPOLD outcomes. There were no significant differences in either VO2mean, MR, GE, or BLadiff (all P > 0.05) between the DPMOD and DPOLD tests. DPMOD execution was associated with a higher RER (P < 0.05). Significant technique-specific differences were found in either the highest and/or the lowest position for all six analyzed joint angles (all P < 0.001). Hence, despite decades of double-poling technique development, which is reflected in the significant biomechanical differences between DPOLD and DPMOD execution, at submaximal work intensity, the modern technique is not more energy efficient than the old-fashioned technique.
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| 34. |
- Elfström, Magnus, et al.
(författare)
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Validation of the Swedish version of the clinical outcomes in routine evaluation outcome measure (CORE-OM)
- 2013
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Ingår i: Clinical Psychology and Psychotherapy. - : Wiley. - 1063-3995 .- 1099-0879. ; 20:5, s. 447-455
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to perform an initial validation of a Swedish translation of the Clinical Outcomes in Routine Evaluation Outcome Measure (CORE-OM). The CORE-OM is a broad self-report instrument of psychological problems, designed as an outcome measure for evaluating the effects of psychological therapy. Participants included a non-clinical group of 229 university students and a clinical group of 619 persons from four primary care sites. The Swedish CORE-OM showed excellent acceptability, high internal consistency and test-retest reliability, as well as acceptable convergent validity. There was strong differentiation of the clinical and non-clinical samples, with the clinical group scoring significantly more psychological problems than the non-clinical group. Sensitivity to change was demonstrated in psychological treatments in primary care. Overall, the psychometric characteristics of the Swedish CORE-OM were very similar to the original UK data. Nevertheless, the validity of the Swedish version needs to be examined more in detail, in larger and more diverse samples. Our results so far, however, provide support for using the Swedish CORE-OM as a psychological problems measure. To our knowledge, there are few other relatively short measures in Swedish that are free to reprint that meet the demands for psychometric properties and utility in primary care settings in which patients typically present a broad range of psychological problems.
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| 35. |
- Ericsson, Per, et al.
(författare)
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Characterization of particulate emissions and methodology for oxidation of particulates from non-diesel combustion systems
- 2008
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Ingår i: SAE Technical Paper. - 400 Commonwealth Drive, Warrendale, PA, United States : SAE International. - 0148-7191.
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Tidskriftsartikel (refereegranskat)abstract
- Tailpipe particulate emissions, i.e., particle number, size distribution and total mass, from a series of four-cylinder engines with 2L displacement and power output of approximately 150 hp have been measured. The engines were in their respective vehicle installation, all midsize vehicles from various manufacturers, and represented different combustion concepts, i.e., port- and direct-injected vehicles and E5 and E85 fuels. The results are compared to post-Euro V emission standards for gasoline and biofuels using diesel as reference. The results show that the type of combustion and fuel significantly affect the particulate formation. In general, direct-injected engines show high particle numbers and mass compared to port-injected engines. The particulate number and total mass can be reduced by using biofuels, e.g., ethanol mixes, instead of gasoline. Moreover, an experimental procedure and setup facilitating precise studies of oxidation of particulates in realistic filter structures by well-controlled gas flow (composition and temperature) and sample (particulate load and temperature) conditions has been developed. The results from this method have been verified by using commercial soot as reference.
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| 36. |
- Hellring, Magnus, et al.
(författare)
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Robust AFR estimation using the ion current and neural networks
- 1999
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Ingår i: SAE transactions. - New York : Society of Automotive Engineers. - 0096-736X. ; 108:03, s. 1585-1589
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Tidskriftsartikel (refereegranskat)abstract
- A robust air/fuel ratio "soft sensor" is presented based on non-linear signal processing of the ion current signal using neural networks. Care is taken to make the system insensitive to amplitude variations, due to e.g. fuel additives, by suitable preprocessing of the signal. The algorithm estimates the air/fuel ratio to within 1.2% from the correct value, defined by a universal exhaust gas oxygen (UEGO) sensor, when tested on steady state test-bench data and using the raw ion current signal. Normalizing the ion current increases robustness but also increases the error by a factor of two. The neural network soft sensor is about 20 times better in the case where the ion current is not normalized, compared with a linear model. On normalized ion currents the neural network model is about 4 times better than the corresponding linear model. Copyright © 1999 Society of Automotive Engineers, Inc.
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| 37. |
- Hellring, Magnus, et al.
(författare)
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Spark advance control using the ion current and neural soft sensors
- 1999
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Ingår i: SAE transactions. - New York : Society of Automotive Engineers. - 0096-736X. ; 108:03, s. 1590-1595
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Tidskriftsartikel (refereegranskat)abstract
- Two spark advance control systems are outlined; both based on feedback from nonlinear neural network soft sensors and ion current detection. One uses an estimate on the location of the pressure peak and the other uses an estimate of the location of the center of combustion. Both quantities are estimated from the ion current signal using neural networks. The estimates are correct within roughly two crank angle degrees when evaluated on a cycle to cycle basis, and roughly within one crank angle degree when the quantities are averaged over consecutive cycles.The pressure peak detection based control system is demonstrated on a SAAB 9000 car, equipped with a 2.3 liter low-pressure turbo charged engine, during normal highway driving. © 1998 Society of Automotive Engineers, Inc.
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| 38. |
- Högman, Marieann, et al.
(författare)
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Differences in nitric oxide airway diffusion after maximum oxygen uptake test in asthmatic and nonasthmatic elite junior cross-country skiers
- 2021
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Ingår i: ERJ Open Research. - : European Respiratory Society (ERS). - 2312-0541. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- Asthma is common in cross-country skiers and is often treated with ß2-agonists and inhaled corticosteroids (ICS). Exhaled nitric oxide is often used to guide ICS treatment in asthma. This study investigated the change in the pulmonary NO dynamics before and after a maximum oxygen uptake (V̇O2-max) test.An extended NO analysis was performed among Swedish elite junior cross-country skiers (n=25), with and without declared asthma, before and after a V̇O2-max test using roller skis. Asthma was declared by six boys and two girls among whom five occasionally used ICS.There were no differences in the baseline NO parameters between those with and without declared asthma. The diffusion capacity over airway wall (DawNO) was 21 (17,25) mL·s−1 (median, quartiles), which is much increased for this age group. After the V̇O2-max test, there were statistically significant differences from the baseline fraction of exhaled nitric oxide (FENO50), NO-flux from airways, DawNO and alveolar NO values; but not in the NO content in airway wall (CawNO) for all subjects together as one group. However, in the asthma group, differences were only seen in the FENO50 and in CawNO.Interestingly, a majority of the subjects had an increase in the DawNO. An increase in DawNO has been found with allergic asthma together with elevated CawNO. The skiers did not have elevated CawNO, which indicates an absence of inflammation in the airway wall. Modelling of lung NO production clearly shows that the asthma among our skiers is distinct from the allergic asthma in non-athletes.
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| 39. |
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| 40. |
- Högman, Marieann, et al.
(författare)
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Skiers with or without asthma have increased airway diffusion rate of NO from the airways : Konferensbidrag, Muntlig presentation med publicerat abstract (Refereegranskat)
- 2020
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Ingår i: European Respiratory Journal. - : European Respiratory Society. - 0903-1936 .- 1399-3003. ; 56:suppl 64
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Tidskriftsartikel (refereegranskat)abstract
- Exercise induced bronchoconstriction (EIB) is common in skiers and often treated with β2-agonists and inhaled corticosteroids (ICS). We examined 25 elite junior cross-country skiers (17 boys and 8 girls, age 18±1 y) pre and post a V̇O2max test to see how NO parameters of the lung changed. A health declaration was filled in and 6 boys and 2 girls declared that they had asthma diagnosed by a physician, whereas 5 of them were on ICS treatment. NO analysis was done with multiple flows (Högman-Meriläinen algorithm) before and within 10 min after the V̇O2max test. FENO50 was at rest 17 (11, 24) ppb (median, quartiles). CANO was 1.5 (1.1, 1.9) ppb, JawNO 0.75 (0.56, 1.55) nL/s, and CawNO 51 (26, 63) ppb. DawNO was 21 (17,25) mL/s, with only three skiers with values in the range of upper and lower quartiles for reference values. There were no differences in NO parameters between those declaring or not declaring asthma. After the V̇O2max test FENO50 decreased by 5 (3, 8) ppb (p<0.001), JawNO with 0.27 (0.15, 0.49) nL/s (p<0.001), CawNO with 6 (-14, 20) ppb (ns), DawNO with 4 (-3, 14) mL/s (p=0.032), while CANO increased by 0.6 (0.1, 1.2) ppb (p=0.006). Interestingly, the majority of participants had an increase in DawNO. An increase in DawNO has been found in allergic asthma together with elevated CawNO. The skiers did not have elevated CawNO, which indicate an absence of inflammation in the airway wall. Should they withhold ICS, since it does not affect DawNO? Modelling of lung NO production clearly shows that the EIB is distinct from allergic asthma.CANO=alveolar NO, JawNO=NO-flux from airways, CawNO=NO content in airway wall, DawNO=diffusion capacity over airway wall
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| 41. |
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| 42. |
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| 43. |
- Johnson, Magnus S.C. 1969, et al.
(författare)
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Expression of scavenger receptor class B type I in gallbladder columnar epithelium.
- 2002
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Ingår i: Journal of gastroenterology and hepatology. - 0815-9319. ; 17:6, s. 713-20
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Tidskriftsartikel (refereegranskat)abstract
- The lipid content of bile may be modified by the gallbladder epithelium. Recent studies indicate that cholesterol can be absorbed from bile and that this can be enhanced by apolipoprotein (apo) A-I. SR-BI is a multifunctional receptor capable of binding a wide array of native or modified lipoproteins, phospholipid or bile acid micelles. As apo A-I is a ligand for scavenger receptor class B type I (SR-BI) we have characterized the expression of this receptor in murine gallbladder.Reverse transcription-polymerase chain reaction (RT-PCR), immunoblotting and immunohistochemistry were used to study SR-BI expression in murine gallbladders. SR-BI expression was also used to examine gallbladders from high-fat-fed wild-type and apo B-100 transgenic mice.SR-BI and SR-BII mRNA are expressed in gallbladder. SR-BI immunoreactivity was localized to the columnar epithelium of the gallbladder. Immunoreactive SR-BI in gallbladder had an estimated molecular weight of 57 kDa, in contrast to the expected 82 kDa. Deglycosylation experiments indicated that the size difference between the two forms of the receptor is due to post-translational modification. Fat feeding of apo B transgenic mice resulted in gallstone formation but had no effect on the abundance of SR-BI.Gallbladder epithelial cells express SR-BI. This opens the possibility that SR-BI may influence the modification of bile in the gallbladder.
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| 44. |
- Johnson, Magnus S.C. 1969, et al.
(författare)
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Interaction of scavenger receptor class B type I with peroxisomal targeting receptor Pex5p.
- 2003
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Ingår i: Biochemical and biophysical research communications. - 0006-291X. ; 312:4, s. 1325-34
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Tidskriftsartikel (refereegranskat)abstract
- Scavenger receptor class B type I (SR-BI) is an HDL receptor that mediates selective HDL lipid uptake. Peroxisomes play an important role in lipid metabolism and peroxisomal targeting signal type 1 (PTS1)-containing proteins are translocated to peroxisomes by the peroxisomal targeting import receptor, Pex5p. We have previously identified a PTS1 motif in the intracellular domain of rat SR-BI. Here, we examine the possible interaction between Pex5p and SR-BI. Expression of a Flag-tagged intracellular domain of SR-BI resulted in translocation to the peroxisome as demonstrated by double labeling with anti-Flag IgG and anti-catalase IgG analyzed by confocal microscopy. Immunoprecipitation experiments with anti-SR-BI antibody showed that Pex5p co-precipitated with SR-BI. However, when an antibody against Pex5p was used for immunoprecipitation, only the 57kDa, non-glycosylated form, of SR-BI co-precipitated. We conclude that the PTS1 domain of SR-BI is functional and can mediate peroxisomal interaction via Pex5p, in vitro.
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| 45. |
- Kanagarajan, Selvaraju, et al.
(författare)
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Production of functional human fetal hemoglobin in Nicotiana benthamiana for development of hemoglobin-based oxygen carriers
- 2021
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Ingår i: International Journal of Biological Macromolecules. - : Elsevier BV. - 0141-8130 .- 1879-0003. ; 184, s. 955-966
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Tidskriftsartikel (refereegranskat)abstract
- Hemoglobin-based oxygen carriers have long been pursued to meet clinical needs by using native hemoglobin (Hb) from human or animal blood, or recombinantly produced Hb, but the development has been impeded by safety and toxicity issues. Herewith we report the successful production of human fetal hemoglobin (HbF) in Nicotiana benthamiana through Agrobacterium tumefaciens-mediated transient expression. HbF is a heterotetrameric protein composed of two identical α- and two identical γ-subunits, held together by hydrophobic interactions, hydrogen bonds, and salt bridges. In our study, the α- and γ-subunits of HbF were fused in order to stabilize the α-subunits and facilitate balanced expression of α- and γ-subunits in N. benthamiana. Efficient extraction and purification methods enabled production of the recombinantly fused endotoxin-free HbF (rfHbF) in high quantity and quality. The transiently expressed rfHbF protein was identified by SDS-PAGE, Western blot and liquid chromatography-tandem mass spectrometry analyses. The purified rfHbF possessed structural and functional properties similar to native HbF, which were confirmed by biophysical, biochemical, and in vivo animal studies. The results demonstrate a high potential of plant expression systems in producing Hb products for use as blood substitutes.
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| 46. |
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| 47. |
- Magnusson, Maria, et al.
(författare)
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DIRA-3D-a model-based iterative algorithm for accurate dual-energy dual-source 3D helical CT
- 2019
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Ingår i: Biomedical Engineering & Physics Express. - : IOP PUBLISHING LTD. - 2057-1976. ; 5:6
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Tidskriftsartikel (refereegranskat)abstract
- Quantitative dual-energy computed tomography may improve the accuracy of treatment planning in radiation therapy. Of special interest are algorithms that can estimate material composition of the imaged object. One example of such an algorithm is the 2D model-based iterative reconstruction algorithm DIRA. The aim of this work is to extend this algorithm to 3D so that it can be used with cone-beams and helical scanning. In the new algorithm, the parallel FBP method was replaced with the approximate 3D FBP-based PI-method. Its performance was tested using a mathematical phantom consisting of six ellipsoids. The algorithm substantially reduced the beam-hardening artefact and the artefacts caused by approximate reconstruction after six iterations. Compared to Alvarez-Macovskis base material decomposition, DIRA-3D does not require geometrically consistent projections and hence can be used in dual-source CT scanners. Also, it can use several tissue-specific material bases at the same time to represent the imaged object.
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| 48. |
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| 49. |
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