| 1. |
- Almhagen, Erik, et al.
(författare)
-
Modelling tissue specific RBE for different radiation qualities based on a multiscale characterization of energy deposition
- 2023
-
Ingår i: Radiotherapy and Oncology. - : Elsevier. - 0167-8140 .- 1879-0887. ; 182
-
Tidskriftsartikel (refereegranskat)abstract
- PurposeWe present the nanoCluE model, which uses nano- and microdosimetric quantities to model RBE for protons and carbon ions. Under the hypothesis that nano- and microdosimetric quantities correlates with the generation of complex DNA double strand breakes, we wish to investigate whether an improved accuracy in predicting LQ parameters may be achieved, compared to some of the published RBE models.MethodsThe model is based on experimental LQ data for protons and carbon ions. We generated a database of track structure data for a number of proton and carbon ion kinetic energies with the Geant4-DNA Monte Carlo code. These data were used to obtain both a nanodosimetric quantity and a set of microdosimetric quantities. The latter were tested with different parameterizations versus experimental LQ-data to select the variable and parametrization that yielded the best fit.ResultsFor protons, the nanoCluE model yielded, for the ratio of the linear LQ term versus the test data, a root mean square error (RMSE) of 1.57 compared to 1.31 and 1.30 for two earlier other published proton models. For carbon ions the RMSE was 2.26 compared to 3.24 and 5.24 for earlier published carbon ion models.ConclusionThese results demonstrate the feasibility of the nanoCluE RBE model for carbon ions and protons. The increased accuracy for carbon ions as compared to two other considered models warrants further investigation.
|
|
| 2. |
|
|
| 3. |
- Bicsak, T A, et al.
(författare)
-
Tissue-type plasminogen activator in rat oocytes : expression during the periovulatory period, after fertilization, and during follicular atresia.
- 1989
-
Ingår i: Endocrinology. - 0013-7227 .- 1945-7170. ; 124:1, s. 187-94
-
Tidskriftsartikel (refereegranskat)abstract
- The regulation of tissue-type plasminogen activator (tPA) in rat oocytes during the periovulatory period, in early embryos, and in oocytes during induced follicular atresia was studied using a quantitative chromogenic substrate assay. Oocytes and early embryos were collected from three ovulation models: 1) intact immature female rats treated with PMSG, followed by hCG 48 h later; 2) hypophysectomized immature rats treated with PMSG, followed by a GnRH agonist (GnRHa) 56 h later; and 3) adult cyclic rats on the mornings of proestrus and estrus and up to 5 days after fertilization. In addition, follicular atresia was induced by either withdrawal of diethylstilbestrol (DES) for 2 days or injection of GnRHa for 2 days in hypophysectomized DES-implanted immature rats. Treatment with PMSG alone did not increase oocyte tPA content (5-20 microIU/oocyte) in either immature rat model, but treatment with either hCG or GnRHa induced meiotic maturation and ovulation and increased tPA activity to 80 and 140 microIU/oocyte 24 h after hCG and GnRHa treatment, respectively. Northern blot analysis of total RNA extracted from oocytes of PMSG-treated rats indicated the presence of a specific tPA message at 22S. tPA levels were low in preovulatory oocytes obtained on proestrus morning and increased in ovulated oocytes on estrus morning. After fertilization, tPA levels remained high in the embryos on days 1-4 of pregnancy, but dropped dramatically on day 5. Furthermore, oocytes from atretic follicles of hypophysectomized DES-implanted rats after either DES withdrawal or GnRHa treatment contained elevated levels of tPA, coincident with germinal vesicle breakdown (GVBD). Immunohistochemical staining revealed tPA antigen only in those oocytes that had undergone apparent meiotic maturation, as confirmed by GVBD. Thus, oocytes contain tPA mRNA and synthesize the active protease under a variety of stimuli which result in GVBD. The observed periovulatory increase in oocyte tPA activity, its maintenance until day 5 of pregnancy, and expression of tPA in nonovulatory oocytes of atretic follicles suggest diverse functions for the oocyte and embryo tPA.
|
|
| 4. |
|
|
| 5. |
- Frisén, Ann, 1963, et al.
(författare)
-
“Doesn’t Everyone Want That? It’s Just a Given”: Swedish Emerging Adults’ Expectations on Future Parenthood and Work/Family Priorities
- 2014
-
Ingår i: Journal of Adolescent Research. - : SAGE Publications. - 0743-5584 .- 1552-6895. ; 29:1, s. 67-88
-
Tidskriftsartikel (refereegranskat)abstract
- This study investigated Swedish emerging adults’ expectations on future parenthood through interviews with 124 Swedish emerging adults who were not yet parents. Thematic analysis showed that most participants were sure they wanted to become parents, but not right now. First, they wanted a stable financial situation, a romantic relationship, and time for self-focus. More women than men talked about parenthood as a social norm and wanted to prioritize both work and family. More men than women wanted to prioritize either work or family before the other. The study showed that Swedish emerging adults postpone, but do not reject, parenthood and that gender differences in expectations on parenthood may contribute to a reproduction of gender inequalities in family life.
|
|
| 6. |
- Helgason, Jon, 1971-, et al.
(författare)
-
Att följa litteraturens värden
- 2015
-
Ingår i: Nationell ämneskonferens i litteraturvetenskap 7-9 maj 2015.
-
Konferensbidrag (refereegranskat)
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Komajda, Michel, et al.
(författare)
-
Relations between professional medical associations and the health-care industry, concerning scientific communication and continuing medical education: a Policy Statement from the European Society of Cardiology.
- 2012
-
Ingår i: European Heart Journal. - : Oxford University Press. - 0195-668X .- 1522-9645. ; 33:5, s. 666-674
-
Tidskriftsartikel (refereegranskat)abstract
- Physicians have an ethical duty to keep up-to-date with current knowledge. Professional medical associations such as the European Society of Cardiology (ESC) support these obligations. In Europe, the costs of continuing medical education (CME) are insufficiently supported from governments and employers; however, medical associations have been criticized for accepting alternative financial support from industry. Medical education and training in research include learning how to assess the quality and reliability of any information. There is some risk of bias in any form of scientific communication including intellectual, professional, and financial and it is essential that in particular, the latter must be acknowledged by full disclosure. It is essential that there is strong collaboration between basic and clinical researchers from academic institutions on the one hand, with engineers and scientists from the research divisions of device and pharmaceutical companies on the other. This is vital so that new diagnostic methods and treatments are developed. Promotion of advances by industry may accelerate their implementation into clinical practice. Universities now frequently exhort their academic staff to protect their intellectual property or commercialize their research. Thus, it is not commercial activity or links per se that have become the target for criticism but the perceived influence of commercial enterprises on clinical decision-making or on messages conveyed by professional medical organizations. This document offers the perspective of the ESC on the current debate, and it recommends how to minimize bias in scientific communications and CME and how to ensure proper ethical standards and transparency in relations between the medical profession and industry.
|
|
