1. |
- Heidegger, A., et al.
(författare)
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Development and inter-laboratory validation of the VISAGE enhanced tool for age estimation from semen using quantitative DNA methylation analysis
- 2022
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Ingår i: Forensic Science International: Genetics. - : Elsevier BV. - 1872-4973. ; 56
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Tidskriftsartikel (refereegranskat)abstract
- The analysis of DNA methylation has become an established method for chronological age estimation. This has triggered interest in the forensic community to develop new methods for age estimation from biological crime scene material. Various assays are available for age estimation from somatic tissues, the majority from blood. Age prediction from semen requires different DNA methylation markers and the only assays currently developed for forensic analysis are based on SNaPshot or pyrosequencing. Here, we describe a new assay using massively parallel sequencing to analyse 13 candidate CpG sites targeted in two multiplex PCRs. The assay has been validated by five consortium laboratories of the VISible Attributes through GEnomics (VISAGE) project within a collaborative exercise and was tested for reproducible quantification of DNA methylation levels and sensitivity with DNA methylation controls. Furthermore, DNA extracts and stains on Whatman FTA cards from two semen samples were used to evaluate concordance and mimic casework samples. Overall, the assay yielded high read depths (> 1000 reads) at all 13 marker positions. The methylation values obtained indicated robust quantification with an average standard deviation of 2.8% at the expected methylation level of 50% across the 13 markers and a good performance with 50 ng DNA input into bisulfite conversion. The absolute difference of quantifications from one participating laboratory to the mean quantifications of concordance and semen stains of remaining laboratories was approximately 1%. These results demonstrated the assay to be robust and suitable for age estimation from semen in forensic investigations. In addition to the 13-marker assay, a more streamlined protocol combining only five age markers in one multiplex PCR was developed. Preliminary results showed no substantial differences in DNA methylation quantification between the two assays, indicating its applicability with the VISAGE age model for semen developed with data from the complete 13-marker tool.
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2. |
- Garcia Carrasco, Alvaro, et al.
(författare)
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Nitrogen removal from plasma-facing components by ion cyclotron wall conditioning in TEXTOR
- 2015
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Ingår i: Journal of Nuclear Materials. - : Elsevier BV. - 0022-3115 .- 1873-4820. ; 463, s. 688-692
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The efficiency of ion cyclotron wall conditioning (ICWC) in the removal of nitrogen from plasma-facing components in TEXTOR was assessed. In two experiments the wall was loaded with nitrogen and subsequently cleaned by ICWC in deuterium and helium. The retention and removal of nitrogen was studied in-situ by means of mass spectrometry, and ex-situ by surface analysis of a set of graphite, tungsten and TZM plates installed on test limiter systems. N-15 rare isotope was used as a marker. The results from the gas balance showed that about 25% of the retained nitrogen was removed after ICWC cleaning, whereas surface analysis of the plates based on ToF-HIERDA showed an increase of the deposited species after the cleaning. This indicates that during ICWC operation on carbon devices, nitrogen is not only pumped out but also transported to other locations on the wall. Additionally, deuterium surface content was studied before and after ICWC cleaning.
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3. |
- Nilsson, Lars J, et al.
(författare)
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Energy policy and the role of bioenergy in Poland
- 2006
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Ingår i: Energy Policy. - : Elsevier BV. - 1873-6777 .- 0301-4215. ; 34:15, s. 2263-2278
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Tidskriftsartikel (refereegranskat)abstract
- Poland, as many other countries, has ambitions to increase the use of renewable energy sources. In this paper, we review the current status of bioenergy in Poland and make a critical assessment of the prospects for increasing the share of bioenergy in energy supply, including policy implications. Bioenergy use was about 4% (165PJ) of primary energy use (3900PJ) and 95% of renewable energy use (174PJ) in 2003, mainly as firewood in the domestic sector. Targets have been set to increase the contribution of renewable energy to 7.5% in 2010, in accordance with the EU accession treaty, and to 14% in 2020. Bioenergy is expected to be the main contributor to reaching those targets. From a resource perspective, the use of bioenergy could at least double in the near term if straw, forestry residues, wood-waste, energy crops, biogas, and used wood were used for energy purposes. The long-term potential, assuming short rotation forestry on potentially available agricultural land is about one-third, or 1400 PJ, of current total primary energy use. However, in the near term, Poland is lacking fundamental driving forces for increasing the use of bioenergy (e.g., for meeting demand increases, improving supply security, or further reducing sulphur or greenhouse gas emissions). There is yet no coherent policy or strategy for supporting bioenergy. Co-firing with coal in large plants is an interesting option for creating demand and facilitating the development of a market for bioenergy. The renewable electricity quota obligation is likely to promote such co-firing but promising applications of bioenergy are also found in small- and medium-scale applications for heat production. Carbon taxes and, or, other financial support schemes targeted also at the heating sector are necessary in the near term in order to reach the 7.5% target. In addition, there is a need to support the development of supply infrastructure, change certain practices in forestry, coordinate RD&D efforts, and support general capacity building. The greatest challenge for the longer term lies in reforming and restructuring the agricultural sector. (c) 2005 Elsevier Ltd. All rights reserved.
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4. |
- Racka, K., et al.
(författare)
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Growth of SiC by PVT method in the presence of cerium dopant
- 2013
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Ingår i: Journal of Crystal Growth. - : Elsevier BV. - 0022-0248 .- 1873-5002. ; 377, s. 88-95
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Tidskriftsartikel (refereegranskat)abstract
- The effect of the presence of CeO2 in the source material on the properties of SiC crystals grown by Physical Vapor Transport (PVT) method is investigated. The doping efficiency and, indirectly, the presence of the cerium vapour in the growth atmosphere were examined by study of structural, electrical and optical properties of the crystals. X-ray photoelectron spectroscopy shows that Ce2O3 and CeO2 coexist on the SiC post-growth surfaces. A detectable Ce incorporation is observed only in the last grown part of the crystal.
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