| 11. |
- Motta, M., et al.
(författare)
-
Controllable morphology of flux avalanches in microstructured superconductors
- 2014
-
Ingår i: Physical Review B - Condensed Matter and Materials Physics. - 2469-9950 .- 2469-9969. ; 89:13
-
Tidskriftsartikel (refereegranskat)abstract
- The morphology of abrupt bursts of magnetic flux into superconducting films with engineered periodic pinning centers (antidots) has been investigated. Guided flux avalanches of thermomagnetic origin develop a treelike structure, with the main trunk perpendicular to the borders of the sample, while secondary branches follow well-defined directions determined by the geometrical details of the underlying periodic pinning landscape. Strikingly, we demonstrate that in a superconductor with relatively weak random pinning the morphology of such flux avalanches can be fully controlled by proper combinations of lattice symmetry and antidot geometry. Moreover, the resulting flux patterns can be reproduced, to the finest details, by simulations based on a phenomenological thermomagnetic model. In turn, this model can be used to predict such complex structures and to estimate physical variables of more difficult experimental access, such as the local values of temperature and electric field.
|
|
| 12. |
- Motta, M., et al.
(författare)
-
Enhanced pinning in superconducting thin films with graded pinning landscapes
- 2013
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 102:21
-
Tidskriftsartikel (refereegranskat)abstract
- A graded distribution of antidots in superconducting a-Mo79Ge21 thin films has been investigated by magnetization and magneto-optical imaging measurements. The pinning landscape has maximum density at the sample border, decreasing linearly towards the center. Its overall performance is noticeably superior than that for a sample with uniformly distributed antidots: For high temperatures and low fields, the critical current is enhanced, whereas the region of thermomagnetic instabilities in the field-temperature diagram is significantly suppressed. These findings confirm the relevance of graded landscapes on the enhancement of pinning efficiency, as recently predicted by Misko and Nori.
|
|
| 13. |
- Olsson, Ann, et al.
(författare)
-
Survival of glioma patients in relation to mobile phone use in Denmark, Finland and Sweden
- 2019
-
Ingår i: Journal of Neuro-Oncology. - : Springer. - 0167-594X .- 1573-7373. ; 141:1, s. 139-149
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: Gliomas are the most common cancer of the brain, with a poor prognosis in particular for glioblastoma. In 2014, a study suggested reduced survival in relation to latency of mobile phone use among glioblastoma patients. A joint epidemiological/experimental project to study effects of RF-EMF on tumor development and progression was established. The current analysis relates to the epidemiological part and addresses whether pre-diagnostic mobile phone use was associated with survival among glioma patients.Methods: Glioma cases (n = 806) previously enrolled in a collaborative population-based case–control study in Denmark, Finland and Sweden were followed up for survival. Vital status, date of death, date of emigration, or date last known to be alive was obtained based on registry linkages with a unique personal ID in each country. Cox regression models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI) stratified by country. Covariates investigated were sex, age, education, histology, treatment, anatomic location and marital status.Results: No indication of reduced survival among glioblastoma patients was observed for various measures of mobile phone use (ever regular use, time since start of regular use, cumulative call time overall or in the last 12 months) relative to no or non-regular use. All significant associations suggested better survival for mobile phone users. Results were similar for high-grade and low-grade gliomas.Conclusions: We found no evidence of reduced survival among glioma patients in relation to previous mobile phone use.
|
|
| 14. |
- Tettamanti, Giorgio, et al.
(författare)
-
Long-term effect of mobile phone use on sleep quality : Results from the cohort study of mobile phone use and health (COSMOS)
- 2020
-
Ingår i: Environment International. - : Elsevier BV. - 0160-4120 .- 1873-6750. ; 140
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Effects of radiofrequency electromagnetic field exposure (RF-EMF) from mobile phone use on sleep quality has mainly been investigated in cross-sectional studies. The few previous prospective cohort studies found no or inconsistent associations, but had limited statistical power and short follow-up. In this large prospective cohort study, our aim was to estimate the effect of RF-EMF from mobile phone use on different sleep outcomes.Materials and methods: The study included Swedish (n = 21,049) and Finnish (n = 3120) participants enrolled in the Cohort Study of Mobile Phone Use and Health (COSMOS) with information about operator-recorded mobile phone use at baseline and sleep outcomes both at baseline and at the 4-year follow-up. Sleep disturbance, sleep adequacy, daytime somnolence, sleep latency, and insomnia were assessed using the Medical Outcome Study (MOS) sleep questionnaire.Results: Operator-recorded mobile phone use at baseline was not associated with most of the sleep outcomes. For insomnia, an odds ratio (OR) of 1.24, 95% CI 1.03-1.51 was observed in the highest decile of mobile phone call-time (> 258 min/week). With weights assigned to call-time to account for the lower RF-EMF exposure from Universal Mobile Telecommunications Service (UMTS, 3G) than from Global System for Mobile Communications (GSM, 2G) the OR was 1.09 (95% CI 0.89-1.33) in the highest call-time decile.Conclusion: Insomnia was slightly more common among mobile phone users in the highest call-time category, but adjustment for the considerably lower RF-EMF exposure from the UMTS than the GSM network suggests that this association is likely due to other factors associated with mobile phone use than RF-EMF. No association was observed for other sleep outcomes. In conclusion, findings from this study do not support the hypothesis that RF-EMF from mobile phone use has long-term effects on sleep quality.
|
|
| 15. |
- Tettamanti, Giorgio, et al.
(författare)
-
Prenatal and postnatal medical conditions and the risk of brain tumors in children and adolescents: an international multicenter case-control study.
- 2017
-
Ingår i: Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology. - 1538-7755. ; 26:1
-
Tidskriftsartikel (refereegranskat)abstract
- Previous studies have evaluated the effect of medical diagnostic radiation on brain tumors. Recent cohort studies have reported an increased risk associated with exposure to head CT scans.Information regarding medical conditions, including prenatal and postnatal exposure to medical diagnostic radiation, was obtained from CEFALO, a multicenter case-control study performed in Denmark, Norway, Sweden and Switzerland through face to face interview. Eligible cases of childhood and adolescent brain tumors (CABTs) were aged 7 to 19 years, diagnosed between January 1, 2004 and August 31, 2008 and living in the participating countries (n = 352). The cases were matched by age, sex, and region to 646 population-based controls.Prenatal exposure to medical diagnostic radiation and postnatal exposure to x-rays were not associated with CABTs. A higher risk estimate of CABTs, although not statistically significant, was found for exposure to head CT scan (OR = 1.86, 95% CI 0.82-4.22). The associations with head injury, febrile seizure, fever in the first 12 weeks, and general anesthesia were close to unity.Prenatal or postnatal medical conditions, including medical diagnostic radiation, were not associated with CABTs. Based on small numbers of exposed children, we observed a non-significant increased risk for CT scans of the head.We have presented additional evidence suggesting that exposure to head CT scan may be associated with the occurrence of CABTs.
|
|
| 16. |
- Toledano, Mireille B., et al.
(författare)
-
An international prospective cohort study of mobile phone users and health (COSMOS) : Factors affecting validity of self-reported mobile phone use
- 2018
-
Ingår i: International journal of hygiene and environmental health. - : Elsevier GmbH - Urban und Fischer. - 1438-4639 .- 1618-131X. ; 221:1, s. 1-8
-
Tidskriftsartikel (refereegranskat)abstract
- This study investigates validity of self-reported mobile phone use in a subset of 75 993 adults from the COSMOS cohort study. Agreement between self-reported and operator-derived mobile call frequency and duration for a 3-month period was assessed using Cohen's weighted Kappa (κ). Sensitivity and specificity of both self-reported high (≥10 calls/day or ≥4h/week) and low (≤6 calls/week or <30min/week) mobile phone use were calculated, as compared to operator data. For users of one mobile phone, agreement was fair for call frequency (κ=0.35, 95% CI: 0.35, 0.36) and moderate for call duration (κ=0.50, 95% CI: 0.49, 0.50). Self-reported low call frequency and duration demonstrated high sensitivity (87% and 76% respectively), but for high call frequency and duration sensitivity was lower (38% and 56% respectively), reflecting a tendency for greater underestimation than overestimation. Validity of self-reported mobile phone use was lower in women, younger age groups and those reporting symptoms during/shortly after using a mobile phone. This study highlights the ongoing value of using self-report data to measure mobile phone use. Furthermore, compared to continuous scale estimates used by previous studies, categorical response options used in COSMOS appear to improve validity considerably, most likely by preventing unrealistically high estimates from being reported.
|
|
