| 1. |
- Alakangas, Lena, et al.
(författare)
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StopOx : Utilization Of Industrial Residuals For Prevention Of Sulfide Oxidation In Mine Waste
- 2019
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report is the outcome of the SIP STRIM projectStopOx-Utilization of industrial residuals for prevention of sulfide oxidation in mine waste implemented at Applied geochemistry, Luleå University of Technology running from 2015 to 2018. Boliden Mineral has been partner and co-funder of the project. Other partners in the project were Cementa, Dragon Mining, MEROX, Nordkalk, and SP Processum. The overall aim of the project was to develop prevention technologies to reduce the sulfide oxidation in mine waste, during and after operation, and thereby reduce the generation of acid mine drainage. The StopOx project has been focusing on sulfidic mine waste from the Boliden area which were disposed of and are causing acid mine drainage or have the potential. Industrial residues/products were supplied by BillerudKorsnäs, Cementa, MEROX, and Nordkalk. The report consists of chapters based on three subprojects.Chapter 1. IntroductionChapter 2. Inhibition technology with aim to minimize waste rock oxidation during operations by using residues from other industries (passivation of sulfidic surfaces by the formation of secondary minerals)Chapter 3. The suitability of green liquor dregs as substitutes for or additives to till in a sealing layer as part of a cover systemChapter 4. Weathering of waste rock under changing chemical conditionsThe research described in chapters 2 and 3 was performed by Ph.D. students and will continue until 2021, while the subproject in chapter 2 ended in 2018.
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| 2. |
- Alger, Susanne, 1967-
(författare)
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Licence to drive : the importance of reliability for the validity of the Swedish driving licence test
- 2019
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: The Swedish driving licence test is a criterion-referenced test resulting in a pass or fail. It currently consists of two parts - a theory test with 65 multiple-choice items and a practical driving test where at least 25 minutes are spent driving in traffic. It is a high-stakes test in the sense that the results are used to determine whether the test-taker should be allowed to drive a car without supervision. As the only other requirements for obtaining a licence is a few hours of hazard education (and a short introduction if you intend to drive with a lay instructor) it is important that the test result, in terms of pass or fail, is reliable and valid. If this is not the case it could have detrimental effects on traffic safety. Examining all relevant aspects is beyond the scope of this licentiate thesis so I have focused on reliability.Methods Reliability for both the theoretical and practical test results was examined. As these are very different types of tests the types of reliability examined also differed. In order to examine inter-rater reliability of the driving test 83 examiners were accompanied by one of five selected supervising examiners for a day of tests. All in all 535 tests were conducted with two examiners assessing the same performance. At the end of the day the examiners compared notes and tried to determine the reason for any inconsistencies. Both examiners and students also filled in questionnaires with questions about background and preparation. As for studying decision consistency and decision accuracy of the theory test, three test versions (a total of around 12,000 tests) were examined with the help of methods devised by Subkoviak (Subkoviak, 1976, 1988) and Hanson & Brennan (Brennan, 2004; Hanson & Brennan, 1990).Results The results from two research studies concerning reliability were presented. Study I focused on inter-rater reliability in the driving test and in 93 per cent of cases the examiners made the same assessment. For the tests where their opinions differed there was no correlation to any of the background variables or other variables examined except for three, which had logical explanations and did not constitute a problem. Although there were cases where the differences were due to different stances on matters of interpretation the most common suggested cause was the placement in the car (back seat vs. front seat). Although the supervising examiners gave both praise and criticism as to how the test was carried out the study does not answer the question whether the tests were equal in terms of composition and difficulty.In Study II the focus was on decision consistency and decision accuracy in the theory test. Three versions of the theory tests were examined and, on the whole, found to be fairly similar in terms of item difficulty and score distribution, but the mean was so close to the cut-score (i.e. the score required to pass) that the pass rate differed somewhat between versions. Agreement coefficients were around .80 for all test versions (between .79 and .82 depending on method). Classification accuracy indicated an .87 probability of a correct classification.Conclusion It is important to examine the reliability and validity of the driving licence test since a misclassification can have serious consequences in terms of traffic safety. In the studies included here the rate of agreement between examiners is deemed as satisfactory. It would be preferable if the classification consistency and classification accuracy, as estimated by the methods used, were higher for the theory test, given its importance.While reliability in terms of agreement between raters/examiners or consistency and accuracy of classification are routinely examined in other contexts, such as large-scale educational testing, this is not often done for the driving licence tests. At the same time, the methods used here can be transferred to contexts where such properties are generally not examined. Collecting information about test-takers and examiners, like in Study I, can provide evidence concerning possible bias.Examining to what extent decisions are consistent is one important aspect of collecting evidence that shows that test results can be used to draw conclusions about driver competence. Still, regardless of outcome, validation is a process that never ends. There is always reason to examine various aspects and make further improvements. There are also many other relevant aspects to examine. A prerequisite for the validity of the score interpretation of a criterion-referenced test like this one is that the cut-score is appropriate and the content relevant. This should therefore be the subject of further research as the validation process continues.
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| 3. |
- Köpsén, Susanne, 1952-, et al.
(författare)
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The practice of supervision for professional learning : the exampel of future forensic specialists
- 2015
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Ingår i: Studies in Continuing Education. - London : Routledge. - 0158-037X .- 1470-126X. ; 37:1, s. 30-46
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Tidskriftsartikel (refereegranskat)abstract
- Supervision intended to support learning is of great interest in professional knowledge development. No single definition governs the implementation and enactment of supervision because of different conditions, intentions, and pedagogical approaches. Uncertainty exists at a time when knowledge and methods are undergoing constant development. This situation affects professions with high demands on precision and safety, and thus supervision and learning. The aim of this article is to explore the practice of supervision for learning professional knowledge of forensic specialists. The context is the Swedish National Laboratory of Forensic Science internal training program, which focuses on learning in daily work when the forensic trainee is assigned a supervisor. Ethnographic studies of supervisors and trainees in different forensic specialties were conducted. Practice theory is used to understand how supervision is planned and implemented to support professional development. Findings show that supervision by seasoned professional forensic specialists is significant for trainee learning. However, supervision is arranged, and performed differently, indicating various conditions for learning. Furthermore, the material set-ups of the professional practice prefigure the practice of supervision. Supervision is an area of expertise that needs to be cultivated and learned to maintain highly specialized professional knowledge in current time of change and uncertainty.
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| 4. |
- Manousou, Sofia, 1979, et al.
(författare)
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A Paleolithic-type diet results in iodine deficiency: a 2-year randomized trial in postmenopausal obese women.
- 2018
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Ingår i: European journal of clinical nutrition. - : Springer Science and Business Media LLC. - 1476-5640 .- 0954-3007. ; 72:1, s. 124-129
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Tidskriftsartikel (refereegranskat)abstract
- Different diets are used for weight loss. A Paleolithic-type diet (PD) has beneficial metabolic effects, but two of the largest iodine sources, table salt and dairy products, are excluded. The objectives of this study were to compare 24-h urinary iodine concentration (24-UIC) in subjects on PD with 24-UIC in subjects on a diet according to the Nordic Nutrition Recommendations (NNR) and to study if PD results in a higher risk of developing iodine deficiency (ID), than NNR diet.A 2-year prospective randomized trial in a tertiary referral center where healthy postmenopausal overweight or obese women were randomized to either PD (n=35) or NNR diet (n=35). Dietary iodine intake, 24-UIC, 24-h urinary iodine excretion (24-UIE), free thyroxin (FT4), free triiodothyronine (FT3) and thyrotropin (TSH) were measured at baseline, 6 and 24 months. Completeness of urine sampling was monitored by para-aminobenzoic acid and salt intake by urinary sodium.At baseline, median 24-UIC (71.0μg/l) and 24-UIE (134.0μg/d) were similar in the PD and NNR groups. After 6 months, 24-UIC had decreased to 36.0μg/l (P=0.001) and 24-UIE to 77.0μg/d (P=0.001) in the PD group; in the NNR group, levels were unaltered. FT4, TSH and FT3 were similar in both groups, except for FT3 at 6 months being lower in PD than in NNR group.A PD results in a higher risk of developing ID, than a diet according to the NNR. Therefore, we suggest iodine supplementation should be considered when on a PD.European Journal of Clinical Nutrition advance online publication, 13 September 2017; doi:10.1038/ejcn.2017.134.
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| 5. |
- Nyström, Ingalill, 1969, et al.
(författare)
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FT-Raman Analyses of Blue Dyes Stuff Common in Swedish Folk Art from Hälsingland during 18th and 19th Century
- 2016
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Ingår i: Chemical Sciences Journal. - : OMICS Publishing Group. - 2150-3494. ; 7:2, s. 4-
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Tidskriftsartikel (refereegranskat)abstract
- The overall aim of this study is to gain a better understanding of the historic use of woad in Sweden in the18th and 19th centuries. A key question is, whether it is possible to distinguish between indigo from woad andexotic indigo using Raman spectroscopy? Reference samples prepared according to historic recipes using woad,exotic indigo, logwood and brazilwood - were used to dye different textile fibres - cotton, wool and linen. In addition,various reference compounds - indigotin, indirubin, kaempferol, luteolin, 3-hydroxyflavone and tryptanthrin - as wellas the ‘flower’ of the woad dye bath were analysed to identify specific fingerprint regions for each compound. Bluethreads from four historic textiles - a skirt and three rag balls - from the region of Hälsingland were then analysedin comparison to the references. A specific peak at 993 cm-1 was identified in the spectra taken from the flower ofthe woad vat, which we suggest possibly arises from 3-hydroxyflavone. DSA-ToF-MS analysis suggests flavoneglycosidesas possible candidates. However, cellulosic substrates show a broad vibration at 999 cm-1 overlappingthe flavone signature, thus rendering it non-diagnostic, but it might be possible to use this peak in Raman analysessupported by mass spectrometry to distinguish between indigo from woad and exotic indigo if the substrate is woolor if it is a pigment. Raman analyses of the historic samples identify the colourants as indigo and possibly woad andlogwod mixed with brazilwood.
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| 6. |
- Nyström, Ingalill, 1969, et al.
(författare)
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FT-Raman analyses of dyes and lac pigments in folk arts and crafts in the interiors of Decorative Farmhouses of Hälsingland, Sweden, UNESCO World Heritage
- 2015
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Ingår i: Book of abstracts. 8th International Conference on the Application of Raman spectroscopy in Art and Archaeology Wroclaw 1-5 September 2015, Polen.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This pilot study is about method development using FT-Raman supplemented with computational methods for analyzing dyes and lac pigments used in folk art and craft from Hälsingland, Sweden, during the 18th and 19th century. The study is part of an interdisciplinary four years long project funded by the Swedish Research Council (Vetenskapsrådet). Conservation scientists, chemists, physicists, conservators, art historians and ethnologists from different Swedish universities are collaborating to make a holistic approach and material characterization of wall paintings, painted wall-hangings, decorated wooden furniture and patterned textiles in Decorated Farmhouses of Hälsingland, UNESCO World Heritage since 2012. Spectroscopic methods combined with historic sources are used to understand the materials and the context and time when these artefacts were made. The interdisciplinary collaboration is essential and in this way, new and deeper knowledge of the paint, coatings, painting techniques and dyeing methods in the 18th and 19th century Swedish folk art and handicrafts can be obtained. The relevant research questions span over a wide range, for example about the existence and time frame of woad and turkish red dye. Suitable materials for characterization are for example clothing, which are often possible to date historically due embroidered monograms. Therefore, the material characterization of clothing dyes may shed light on the usage and distribution of various folk art techniques. In the pilot study we present different historic dyestuff such as safflower, cochineals, madder, turkish red, brazilwood, fustic, birch leaves, weld, turmeric, woad, indigo and indigo carmine - all common in Sweden during this period. The dye references were made according to old Swedish recipes. Different textile fibres - cotton, wool and linen/flax - were dyed. In addition various colouring matters - for example purpurin, alizarin, atranorin, orcein, myricetin, luteolin, quercetin, rhamnetin, emodin, crocin, curcummin, kaempferol, indigotin and indirubin - were tested to identify specific fingerprint regions for each dye. In order to assist the interpretation of the vibrational spectra of the samples, computational methods were performed. A typical case study is presented below: threads from an authentic textile, a blue skirt from early 19th century Delsbo parish, were analyzed using FT-Raman spectroscopy. The spectra were then compared with reference spectra. The Raman spectrum of a blue colored linen warp thread is shown together with the spectrum of pure indigotin as a reference (Figure 1). Preliminary results indicate that we are able to identify the main peaks as originating from indigotin in addition background from the linen fibre, suggesting indigo as the dye. Woad was also a common dye during the 18th and 19th century in Sweden [1]. Different from indigo, woad may also contain kaempferol. The comparison with reference spectra however did not yield a match in the fingerprint regions of kaempferol at f.ex. 1188 cm-1 and 1606 cm-1 [2, 3]. Therefore we may exclude woad as an ingredient in the colouring dye of this specific piece of clothing. Historic sources from 18th century usually mention woad as an additional ingredient in the indigo vat to catalyze and help the bacterial fermentation process [4, 5]. During 19th century though, woad is more seldom mentioned as an ingredient and perhaps this is an example of a more modern indigo vat. Other preliminary results shows that almost all pure colouring matters and some of the dyed textile fibres are easy to analyze with FT-Raman. However, it is difficult to analyse red dyes with this method. Furthermore, wool sometimes complicates the analyses. Therefore, we will continue using FT-Raman analyses and the computational models, supplemented with other analytical methods such as SERS and field-free APCI-TOF MS. References [1] Linders, J. Swenska Färge-konst: med Indlandske örter, gäs, blommor, blad, löf, barkar, rötter, wexter och mineraler. Stockholm: Johan Laur. Horrn, Kungliga Antiquit. Archivi Boktr., 1720. [2] Nyström, I. Bonadsmåleri under lupp: spektroskopiska analyser av färg och teknik i sydsvenska bonadsmålningar 1700-1870. Gothenburg Studies in Conservation 29. Göteborgs Universitet: Acta Universitatis Gothoburgensis, 2012. [3] Nyström, I. Spectroscopic analyses of artists' pigments and materials used in Southern Swedish painted wall hangings from the 18th and 19th centuries. Studies in Conservation. Maney, 2014. [4] Hurry, J. B. The woad plant and its dye. London: Oxford University Press, H. Milford (Repr. ed. Clifton New Jersey: Augustus M Kelley Pubs. june 1973), 1930. [5] Cardon, D. Natural dyes: sources, tradition, technology and science. London, Archetype, 2007. Acknowledgment This work is financially supported by the Swedish Research Council, Vetenskapsrådet.
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