| 1. |
|
|
| 2. |
- Gasic, D., et al.
(författare)
-
Retrospective estimation of heart and lung doses in pediatric patients treated with spinal irradiation
- 2018
-
Ingår i: Radiotherapy and Oncology. - : Elsevier BV. - 0167-8140. ; 128:2, s. 209-213
-
Tidskriftsartikel (refereegranskat)abstract
- Background and purpose: The purpose of this study was to investigate whether treatment information from medical records can be used to estimate radiation doses to heart and lungs retrospectively in pediatric patients receiving spinal irradiation with conventional posterior fields. Material and methods: An algorithm for retrospective dosimetry in children treated with spinal irradiation was developed in a cohort of 21 pediatric patients with available CT-scans and treatment plans. We developed a multivariable linear regression model with explanatory variables identifiable in case note review for retrospective estimation of minimum, maximum, mean and V-10%-V-80% doses to the heart and lungs. Doses were estimated for both linear accelerator (Linac) and Co-60 radiation therapy modalities. Results: Age and spinal field width were identified as statistically significant predictors of heart and lung doses in multivariable analyses (p < 0.01 in all models). Models showed excellent predictive performance with R-2 = 0.70 for mean heart dose and 0.79 for mean lung dose, for Linac plans. In leave-one-out cross-validation analysis the average difference between predicted and actual mean heart dose was 6.7% and 7.6% of the prescription dose for Linac and Co-60 plans, respectively, and 5.2% and 4.9% for mean lung dose. Due to the small sample size and large inter-patient variation in heart and lung dose, prospective studies validating these findings are highly warranted. Conclusions: The models presented here provide retrospective estimates of heart and lung doses for historical cohorts of pediatric patients, thus facilitating studies of long-term adverse effects of radiation. (C) 2018 Elsevier B.V. All rights reserved.
|
|
| 3. |
- Mikkelsen, T N, et al.
(författare)
-
Experimental design of multifactor climate change experiments with elevated CO2, warming and drought: the CLIMAITE project
- 2008
-
Ingår i: Functional Ecology. - : Wiley. - 1365-2435 .- 0269-8463. ; 22:1, s. 185-195
-
Tidskriftsartikel (refereegranskat)abstract
- Recent findings indicate that the interactions among CO2, temperature and water can be substantial, and that the combined effects on the biological systems of several factors may not be predicted from experiments with one or a few factors. Therefore realistic multifactorial experiments involving a larger set of main factors are needed. We describe a new Danish climate change-related field scale experiment, CLIMAITE, in a heath/grassland ecosystem. CLIMAITE is a full factorial combination of elevated CO2, elevated temperature and prolonged summer drought. The manipulations are intended to mimic anticipated major environmental changes at the site by year 2075 as closely as possible. The impacts on ecosystem processes and functioning (at ecophysiological levels, through responses by individuals and communities to ecosystem-level responses) are investigated simultaneously. The increase of [CO2] closely corresponds with the scenarios for year 2075, while the warming treatment is at the lower end of the predictions and seems to be the most difficult treatment to increase without unwanted side effects on the other variables. The drought treatment follows predictions of increased frequency of drought periods in summer. The combination of the treatments does not create new unwanted side effects on the treatments relative to the treatments alone.
|
|
| 4. |
|
|
| 5. |
- Brodin, N. Patrik, et al.
(författare)
-
Life years lost-comparing potentially fatal late complications after radiotherapy for pediatric medulloblastoma on a common scale
- 2012
-
Ingår i: Cancer. - : Wiley. - 1097-0142 .- 0008-543X. ; 118:21, s. 5432-5440
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The authors developed a framework for estimating and comparing the risks of various long-term complications on a common scale and applied it to 3 different techniques for craniospinal irradiation in patients with pediatric medulloblastoma. METHODS: Radiation dose-response parameters related to excess hazard ratios for secondary breast, lung, stomach, and thyroid cancer; heart failure, and myocardial infarction were derived from large published clinical series. Combined with age-specific and sex-specific hazards in the US general population, the dose-response analysis yielded excess hazards of complications for a cancer survivor as a function of attained age. After adjusting for competing risks of death, life years lost (LYL) were estimated based on excess hazard and prognosis of a complication for 3-dimensional conformal radiotherapy (3D CRT), volumetric modulated arc therapy (VMAT), and intensity-modulated proton therapy (IMPT). RESULTS: Lung cancer contributed most to the estimated LYL, followed by myocardial infarction, and stomach cancer. The estimates of breast or thyroid cancer incidence were higher than those for lung and stomach cancer incidence, but LYL were lower because of the relatively good prognosis. Estimated LYL ranged between 1.90 years for 3D CRT to 0.28 years for IMPT. In a paired comparison, IMPT was associated with significantly fewer LYL than both photon techniques. CONCLUSIONS: Estimating the risk of late complications is associated with considerable uncertainty, but including prognosis and attained age at an event to obtain the more informative LYL estimate added relatively little to this uncertainty. Cancer 2012. (c) 2012 American Cancer Society.
|
|
| 6. |
- Coulson, S. J., et al.
(författare)
-
Introduction of invertebrates into the High Arctic via imported soils: the case of Barentsburg in the Svalbard
- 2013
-
Ingår i: Biological Invasions. - : Springer Science and Business Media LLC. - 1387-3547 .- 1573-1464. ; 15:1, s. 1-5
-
Tidskriftsartikel (refereegranskat)abstract
- Forty six species of invertebrate were collected from the manure enriched imported soils below the abandoned cow sheds in the Russian mining town of Barentsburg, Svalbard. Of these, 11 (24 %) were new records for Svalbard, including Collembola, gamasid mites, Enchytraeidae and the first identified Lumbricidae. Many of the new records are species not frequently observed in the Arctic. It is hypothesized that these species arrived with the chernozem soils imported to Barentsburg for the greenhouses from central or southern European Russia, or with livestock. The observations presented here are the first records of human invertebrate introductions establishing in Svalbard outside of dwellings. It is not believed that the majority of new species records described present an immediate threat to the ecology of Svalbard but they may, especially Deuteraphorura variabilis, establish in the nutrient enriched floral communities beneath bird cliffs characteristic of Svalbard.
|
|
| 7. |
- Coulson, S. J., et al.
(författare)
-
The invertebrate fauna of anthropogenic soils in the High-Arctic settlement of Barentsburg, Svalbard
- 2013
-
Ingår i: Polar Research. - : Norwegian Polar Institute. - 0800-0395 .- 1751-8369. ; 32
-
Tidskriftsartikel (refereegranskat)abstract
- The terrestrial environment of the High Arctic consists of a mosaic of habitat types. In addition to the natural habitat diversity, various human-influenced types may occur. For the resident invertebrate fauna, these anthropogenic habitats may be either unusually favourable or detrimental. In the town of Barentsburg, Svalbard, soils were imported for the greenhouses from southern Russia. These soils were subsequently discarded outside the greenhouses and have become augmented with manure from the cowsheds. Both the greenhouse and the cowsheds are now derelict. This site represents an unusually nutrient-rich location with considerable development of organic soils, in stark contrast to the naturally forming organic soils in Svalbard, which are typically thin and nutrient poor. Few previous studies have examined the soil invertebrate communities of human-disturbed or -created habitats in the Arctic. In an often nutrient-poor terrestrial environment, it is unclear how the invertebrate fauna will react to such nutrient enhancement. In these soils, 46 species of invertebrates were determined. Eleven species have not been recorded from other habitats in Svalbard and are hence likely to have been introduced. The native species assemblage in the anthropogenic soils was not atypical for many natural sites in Svalbard. Despite the enriched organic soils and highly ameliorated winter temperature conditions, the soil invertebrate fauna biodiversity does not appear to be enhanced beyond the presence of certain probably introduced species.
|
|
| 8. |
|
|
