| 1. |
- Tiensuu, Kiira, et al.
(författare)
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RAVEN: a student rocket program at Luleå University of Technology, Sweden
- 2021
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Ingår i: IAC 2021 Congress Proceedings, 72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates. - : International Astronautical Federation (IAF).
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Konferensbidrag (refereegranskat)abstract
- RAVEN, Rocketry and Aerospace Vehicle Engineering in Norrbotten, is the first rocket project at Luleå University of Technology (LTU), Sweden. The project started in early 2020, and it aims to design, build, test and launch a hybrid propulsion rocket. The initial objectives are to reach an altitude of 10 km with an accompanying payload of 10 kg. The RAVEN team is based at the Kiruna Space Campus and consists of approximately 30 graduate students. The main goal of the first RAVEN rocket is to demonstrate its technology. The team is designing the entire rocket from scratch, including the hybrid propulsion system that uses nitrous oxide as the oxidising agent and paraffin as the solid fuel component, to produce approximately 6 kN of thrust. A modular rocket structure will offer customisation, enabling simple design changes in future iterations. Thus, the layout allows individual subsystems to be re-designed without changes directly affecting others. The project is meant to create a foundation for future student and research rocket projects at LTU. The follow-up developments could further iterate on the first rocket design, increasing hands-on education and providing more collaboration opportunities between the university and the aerospace industry – and eventually provide an in-house platform for research and education at the university or even for commercial start-ups. The infrastructure and resources, such as the proximity to the Esrange Space Center launch facility and support from the university and industry, make Northern Sweden an ideal location to establish a continuous rocket program.
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| 2. |
- Björklund, Filip, et al.
(författare)
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Adverse Effects, Smoking, Alcohol Consumption, and Quality of Life during Long-Term Oxygen Therapy : A Nationwide Study
- 2022
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Ingår i: Annals of the American Thoracic Society. - 2325-6621. ; 19:10, s. 1677-1686
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Tidskriftsartikel (refereegranskat)abstract
- Rationale: Long-term oxygen therapy (LTOT) is prescribed for at least 15 hours per day and often used by patients for several years, but knowledge is limited regarding adverse effects, risk exposures, and health-related quality of life (HrQoL) among those treated. Objectives: To determine the prevalence of adverse effects, smoking, and alcohol consumption and their relations to HrQoL among patients treated with LTOT. Methods: This was a cross-sectional survey of a randomized sample of adults with ongoing LTOT in the Swedish National Registry for Respiratory Failure (Swedevox). Patient characteristics and the prevalence of 26 prespecified adverse effects, smoking, and alcohol consumption, were compared between respondents with better and worse HrQoL on the chronic obstructive pulmonary disease assessment test. Results: A total of 151 respondents were included (mean age, 74.7 yr [standard deviation, 8.6 yr]; 58.9% women; median LTOT duration, 2.2 yr [interquartile range, 1.0-3.8 yr]). Characteristics upon starting LTOT were similar between respondents and nonrespondents. Active smoking was very rare (n = 4, 2.6%). For alcohol use, 67.2% of participants reported no consumption during an average week, whereas risk use was reported by 25.8% of men and 16.9% of women. The most prevalent adverse effects were reduced mobility or physical activity (70.9%), dry mouth (69.5%), congestion or nasal drip (61.6%), increased tiredness (57.0%), and dry nose (53.0%). Patients with higher numbers of total and systemic adverse effects experienced worse HrQoL, whereas no associations were found for smoking status or alcohol consumption. The majority (54.8%) of adverse effects were untreated and unreported to health professionals. Conclusions: Adverse effects are common among patients with LTOT and are associated with worse HrQoL. As the majority of adverse effects had not been discussed or treated, structured assessment and management of risk exposures and adverse effects is warranted.
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| 3. |
- Björklund, Filip, et al.
(författare)
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Breathlessness and exercise performance to predict mortality in long-term oxygen therapy : The population-based DISCOVERY study
- 2023
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Ingår i: Respiratory Medicine. - : Elsevier. - 0954-6111 .- 1532-3064. ; 216
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Patients with chronic respiratory failure treated with long-term oxygen therapy (LTOT) often have severe breathlessness, impaired exercise performance, and high but variable mortality that is difficult to predict. We aimed to evaluate breathlessness and exercise performance upon starting LTOT as predictors of overall and short-term mortality.METHODS: This was a longitudinal, population-based study of patients who initiated LTOT between 2015 and 2018 in Sweden. Breathlessness was measured using the Dyspnea Exertion Scale, and exercise performance using the 30s-Sit-To-Stand test. Associations with overall and three-month mortality were analyzed using Cox-regression. Subgroup analyses were performed for patients with chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD) respectively. The predictive capacity of models was assessed using a C-statistic.RESULTS: A total of 441 patients (57.6% female, aged 75.4 ± 8.3 years) were analyzed, of whom 141 (32%) died during a median follow-up of 260 (IQR 75-460) days. Both breathlessness and exercise performance were independently associated with overall mortality in the crude models, but only exercise performance remained independently associated with overall mortality when models were adjusted for other predictors, when short-term mortality was analyzed, or when breathlessness and exercise capacity were analyzed concurrently. The multivariable model including exercise performance but not breathlessness provided a relatively high predictive capacity for overall mortality, C-statistic 0.756 (95% CI 0.702-0.810). Similar results were seen in the COPD and ILD subgroups.CONCLUSION: Exercise performance as measured by the 30s-STS may be useful to identify patients with higher mortality on LTOT for optimized management and follow-up.
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| 4. |
- Björklund, Filip, et al.
(författare)
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Breathlessness and exercise performance to predict mortality in long-term oxygen therapy
- 2023
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Ingår i: European Respiratory Journal. - : European Respiratory Society. - 0903-1936 .- 1399-3003. ; 62:Suppl. 67
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Background: Patients with chronic respiratory failure treated with long-term oxygen therapy (LTOT) often have severe breathlessness, impaired exercise performance, and high but variable mortality that is difficult to predict. We aimed to evaluate breathlessness and exercise performance upon starting LTOT as predictors of overall and short-term mortality.Methods: This was a longitudinal, population-based study of patients who initiated LTOT between 2015-2018 in Sweden. Breathlessness was measured using the Dyspnea Exertion Scale, and exercise performance using the 30s-Sit-To-Stand test. Associations with overall and three-month mortality were analyzed using Cox-regression. Subgroup analyses were performed for patients with COPD and ILD respectively. The predictive capacity of models was assessed using a C-statistic.Results: A total of 441 patients (57.6% female, aged 75.4±8.3 years) were analyzed. Both breathlessness and exercise performance were independently associated with overall mortality in the crude models, but only exercise performance remained independently associated with overall mortality when models were adjusted for other predictors, when three-month mortality was analyzed, or when breathlessness and exercise capacity were analyzed concurrently. The multivariable model including exercise performance but not breathlessness provided a relatively high predictive capacity for overall mortality, C-statistic 0.756 (95% CI 0.702-0.810). Similar results were seen in the COPD and ILD subgroups.Conclusion: Exercise performance as measured by the 30s-STS may be useful to identify patients with higher mortality on LTOT for optimized management and follow-up.
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| 5. |
- Björklund Svensson, Jonas, et al.
(författare)
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Double-bunches for two-color soft X-ray free-electron laser at the MAX IV Laboratory
- 2018
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Ingår i: Proceedings of FEL2017, Santa Fe, NM, USA. - 9783954501793 ; , s. 269-272
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The ability to generate two-color free-electron laser (FEL) radiation enables a wider range of user experiments than just single-color FEL radiation. There are different schemes for generating the two colors, the original being to use a single bunch and two sets of undulators with different K-parameters. An alternative scheme was recently shown, where two separate bunches in the same RF bucket are used for lasing at different wavelengths in a single set of undulators. We here investigate the feasibility of accelerating and compressing a double-bunch time structure generated in the photocathode electron gun for subsequent use in a soft X-ray FEL at the MAX IV Laboratory.
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| 6. |
- Björklund Svensson, Jonas, et al.
(författare)
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Driver-witness-bunches for plasma-wakefield acceleration at the MAX IV Linear Accelerator
- 2017
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Ingår i: IPAC 2017 - Proceedings of the 8th International Particle Accelerator Conference. - 9783954501823 ; , s. 1743-1746
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Beam-driven plasma-wakefield acceleration is an acceleration scheme promising accelerating fields of at least two to three orders of magnitude higher than in conventional radiofrequency accelerating structures. The scheme relies on using a charged particle bunch (driver) to drive a non-linear plasma wake, into which a second bunch (witness) can be injected at an appropriate distance behind the first, yielding a substantial energy gain of the witness bunch particles. This puts very special demands on the machine providing the particle beam. In this article, we use simulations to show that, if driver-witness-bunches can be generated in the photocathode electron gun, the MAX IV Linear Accelerator could be used for plasma-wakefield acceleration.
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| 7. |
- Delgado Verdugo, Alberto
(författare)
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Genetic Aspects of Endocrine Tumorigenesis : A Hunt for the Endocrine Neoplasia Gene
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Endocrine tumors arise from endocrine glands. Most endocrine tumors are benign but malignant variants exist. Several endocrine neoplasms display loss of parts of chromosome 11 or 18, produce hormones and responds poorly to conventional chemotherapeutics. The multiple endocrine neoplasia syndromes are mainly confined to endocrine tumors. This opens the question if there exists a single or several endocrine tumor genes.The aim of the study was to describe genetic derangements in endocrine tumors.Paper I: Investigation of mutational status of SDHAF2 in parathyroid tumors. SDHAF2 is located in the proximity of 11q13, a region that frequently displays loss in parathyroid tumors. We established that mutations in SDHAF2 are infrequent in parathyroid tumors.Paper II: Study of SDHAF2 gene expression in a cohort of benign pheochromocytomas (PCC) (n=40) and malignant PCC (n=10). We discovered a subset of benign PCC (28/40) and all malignant PCC (10/10) with significantly lower SDHAF2 expression. Benign PCC with low SDHAF2 expression and malignant tumors consistently expressing low levels of SDHAF2 were methylated in the promoter region. SDHAF2 expression was restored in vitro after treatment with 5- aza-2-deoxycytidine.Paper III: HumanMethylation27 array (Illumina) covering 27578 CpG sites spanning over 14495 genes were analyzed in a discovery cohort of 10 primary small neuroendocrine tumors (SI-NETs) with matched metastases. 2697 genes showed different methylation pattern between the primary tumor and its metastasis. We identified several hypermethylated genes in key regions. Unsupervised clustering of the tumors identified three distinct clusters, one with a highly malignant behavior.Paper IV: Loss of chromosome 18 is the most frequent genetic aberration in SI-NETs. DNA from SI-NETs were subjected to whole exome capture sequencing and high resolution SNP array. Genomic profiling revealed loss of chromosome 18 in 5 out of 7 SI-NETs. No tumor-specific somatic mutation on chromosome 18 was identified which suggests involvement of other mechanisms than point mutations in SI-NET tumorigenesis.Paper V: The cost for diagnostic genetic screening of common susceptibility genes in PCC is expensive and labor intensive. Three PCC from three patients with no known family history were chosen for exome capture sequencing. We identified three variants in known candidate genes. We suggest that exome-capture sequencing is a quick and cost-effective tool.
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| 8. |
- Lännerström, Johan, et al.
(författare)
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Effects of Plyometric Training on Soft and Hard Surfaces for Improving Running Economy.
- 2021
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Ingår i: Journal of Human Kinetics. - : Sciendo. - 1640-5544 .- 1899-7562. ; 79:1, s. 187-196
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Tidskriftsartikel (refereegranskat)abstract
- The present study investigated the effects of plyometric jump training on hard and soft surfaces on running economy (RE), maximal oxygen uptake (VO2max), running performance and the rate of force development in orienteers. Nineteen orienteers (11 women and 8 men, body mass 61.1 ± 7.3 kg, age 21 ± 5.8 yrs) were randomly stratified based on sex, age, VO2max and RE to plyometric jumping training (8 sessions over 4 weeks) on either a hard or a soft surface. RE, VO2max and running performance were assessed on a treadmill and outdoor on- and off-trail loops. Moreover, ground reaction forces and force development were assessed during a one leg drop-jump test. The training intervention led to an overall 2-7% improvement in treadmill and off-trail RE, independent of the jumping surface and running velocity assessed. These improvements were not explained by force development during drop jump tests, which remained unchanged following the intervention. The changes in time-trial performance were associated with changes in RE. Plyometric training improved RE with no difference between the hard or the soft training surface and improved RE was also independent of the running speed assessed. Furthermore, improved running performance was associated with changes in RE after the intervention.
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| 9. |
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| 10. |
- Thorin, Sara, et al.
(författare)
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Experience and initial measurements of magnetic linearisation in the MAX IV linac bunch compressors
- 2017
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Ingår i: Proceedings of FEL2017, Santa Fe, NM, USA. - 9783954501793 ; , s. 273-275
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The MAX IV Linac is now in routine operation for injection into two storage rings, and as a high-brightness driver for a Short Pulse Facility (SPF). In short-pulse mode the electron bunch is created in a photo cathode gun and compressed in two double achromat bunch compressors that also linearise longitudinal phase space with the second order transfer matrix element T566. T566 in the compressors canbe tweaked with weak sextupoles located at high dispersion. In this paper we present the current experience from operating the bunch compressors at MAX IV and results from initial measurements of longitudinal phase space using our version of the the zero-crossing method.
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