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- Banati, Jozsef, 1960, et al.
(författare)
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Validation of the RELAP5 Model of Ringhals 4 against a Load Step Test at Uprated Power
- 2015
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- ABSTRACTAfter finishing the large component replacement project of the steam generators and the pressurizer, the Unit 4 of the Ringhals Nuclear Power Plant was operated in test mode between 2011 and 2014. In order to reach the ultimate goal of power uprate, and obtain a license for operation at the new nominal conditions, a series of tests had to be accomplished.The R4-QP-101 maneuverability test was performed on 2015-03-03. The test was focusing on evaluation of the system responses for ± 10 % perturbances in the load. The data collected during test provided a good opportunity for verification of the full plant model, which is being developed for the RELAP5/Mod3.3 Patch04 computer code, with incorporation of the new component models.The present Scientific Report introduces the test procedure and shows an overview on the key parameters that are utilized. There is a brief summary given on the applicability field of the computer code. Preparation of the input deck and the nodalization of the primary and secondary sides are touched upon.Strategies applied for achievement of steady-state conditions are addressed in the document. The steady-state results are presented in plotted format, demonstrating how the control system brought the entire unit to stable conditions. The calculated steady-state parameters were very close to the measured plant data, before the transient initiation.A chapter summarizes the results of the validation study using the transient data to simulate the startup test. Quantification of simulation accuracy has proven that the stand-alone RELAP5 thermal-hydraulic model is capable of reproduction of the key features and events of the test. Sufficiently good agreement between the measured and simulated data resulted in a successful verification of the plant model. The Ringhals 4 model is suitable for analysis of other types of transients already in its current state of development. Nevertheless, further refinement in the input is planned as soon as new test data will be available.Keywords: Ringhals 4, Load Step, RELAP5, code validation
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- Millogo, Vinsoun, et al.
(författare)
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Effect of different hand-milking techniques on milk production and teat treatment in Zebu dairy cattle
- 2012
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Ingår i: Tropical Animal Health and Production. - : Springer Science and Business Media LLC. - 0049-4747 .- 1573-7438. ; 44, s. 1017-1025
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the study was to test three different hand-milking techniques ("pull down", "thumb in", and "full hand grip") and their effects on milk production and teat treatment. This is important since milk production in many tropical areas still rely on hand-milking. The study was carried out at a peri-urban farm in the Bobo-Dioulasso area in Burkina Faso. Twelve indigenous Zebu cows in early lactation were used in the study. The sequences of the treatments (hand-milking techniques) and the milkers were balanced for carry-over effects between successive periods and days, respectively. The sequences were constructed by using special Latin squares. Yield and composition of saleable milk was not affected by milking technique but there were differences between the milkers in milk yield. There was also a significant interaction for saleable milk yield between milker and milking technique. Hemoglobin in milk was measured as an indicator of teat damage. The hemoglobin content was numerically higher in post-milking strip milk samples than in saleable milk. It was concluded that the amount of milk removed depends mainly on the milker and how well the milking technique works for the individual milker. No effect of milking technique was observed on teat treatment.
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- Ferreira da Silva, Eduardo, et al.
(författare)
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Heavy metal pollution downstream the abandoned Coval da Mó mine (Portugal) and associated effects on epilithic diatom communities
- 2009
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 407:21, s. 5620-5636
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Tidskriftsartikel (refereegranskat)abstract
- This study examined trace-element concentrations in 39 sediment samples collected in the vicinity of the abandoned Coval da Mó mine, and evaluated the anthropogenic contaminant effects and other environmental variables in the taxonomic composition, structure and morphological changes of benthic diatom communities.The results show the existence of extremely high contamination in Pb, Zn and Cd (the mean values exceed the background values 376, 96 and 19 times, respectively) on the first 2.5 km in the water flow direction. Also Co, Cu, Mn and Ni are present in high concentrations. Dilution by relatively uncontaminated sediment reduces metal concentrations downstream, but Zn concentrations increase downstream Fílvida stream, as a result of several factors such as sewage and agriculture.To evaluate the biological effects caused by Pb, Cd and Zn, three sites were selected. In the stressed environment, near the mining area (C232), diatoms were extremely rare, however there was a slight recovery at site C79 located 2 km downstream. Fragilaria capucina var. rumpens, Fragilaria cf. crotonensis and Achnanthidium minutissimum showed abnormal valves which may be related to high levels of metals.Six km downstream, in Fílvida stream (C85), an increase in species richness and diversity was registered while the relative percentage of valve teratologies was lower. In the absence of OM, nutrients and low pH the diatom community patterns must be attributed to the metal concentration at some sites. Considering that community diversity can be affected by abiotic and biotic variables and valve deformations are caused by a small number of variables, basically metals, and acid conditions, we consider the presence of teratologies as an indication of the presence of metals.
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- Cotter, MA, et al.
(författare)
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Effects of proinsulin C-peptide in experimental diabetic neuropathy: vascular actions and modulation by nitric oxide synthase inhibition
- 2003
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 52:7, s. 1812-1817
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Tidskriftsartikel (refereegranskat)abstract
- Proinsulin C-peptide treatment can partially prevent nerve dysfunction in type 1 diabetic rats and patients. This could be due to a direct action on nerve fibers or via vascular mechanisms as C-peptide stimulates the nitric oxide (NO) system and NO-mediated vasodilation could potentially account for any beneficial C-peptide effects. To assess this further, we examined neurovascular function in streptozotocin-induced diabetic rats. After 6 weeks of diabetes, rats were treated for 2 weeks with C-peptide to restore circulating levels to those of nondiabetic controls. Additional diabetic groups were given C-peptide with NO synthase inhibitor NG-nitro-l-arginine (l-NNA) co-treatment or scrambled C-peptide. Diabetes caused 20 and 16% reductions in sciatic motor and saphenous sensory nerve conduction velocity, which were 62 and 78% corrected, respectively, by C-peptide. l-NNA abolished C-peptide effects on nerve conduction. Sciatic blood flow and vascular conductance were 52 and 41%, respectively, reduced by diabetes (P < 0.001). C-peptide partially (57–66%) corrected these defects, an effect markedly attenuated by l-NNA co-treatment. Scrambled C-peptide was without effect on nerve conduction or perfusion. Thus, C-peptide replacement improves nerve function in experimental diabetes, and the data are compatible with the notion that this is mediated by a NO-sensitive vascular mechanism.
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- Blanck, Sara, 1980-
(författare)
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Teaching about the topic of migration : Didactical choices and reconstruction of content when teaching about migration for 10-12 years old pupils
- 2021
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Konferensbidrag (refereegranskat)abstract
- Migration is a timeless and increasing phenomenon that affects societies and everyday life on earth. The public discourse on migration has become more polarized with a diminished space for balanced and evidence-based analyses (IOM, 2019). Migration could be an example of what Larsson (2019) describes as a potentially controversial social issue. Tho, many teachers seem to avoid these kinds of issues or feeling difficulties about how to teach about topics of migration (McIntosh, Todd, & Das, 2019). These difficulties could relate to migration as a, often interdisciplinary topic, with dimensions of both values and knowledge. However, teachers need to be better equipped to teach migration sensitively and effectively across disciplines (McIntosh et al., 2019). One dimension of this equipment could be strengthen teachers´ content knowledge about the phenomenon. If the teaching is based on reconstructed specialized knowledge, it could give pupils´ the opportunity to develop critical thinking and analyses based on evidence. This study aims to examine the educational practice about social issues like migration in social studies from a didactical perspective, according to the reconstruction of content, teachers´ choices, and pupils´ knowledge. In this study, based on educational design research (van den Akker, 2006), the intervention is to support the teachers with specialized knowledge and possibilities to reflect around and transform the content in research- and development circle. The teachers have been tested the planned teaching in three different classrooms, two regular classes and one with newly arrived pupils at age 10-12. The empirical material is analyzed from a didactic approach using a framework of Klafkis Categorical Bildung (1985/2001) and the educational practice of Carlgren (2015) to understand the relations between content, teachers didactical choices, and pupils´ knowledge. The results are analyzed according to pupils´ possibilities of developing knowledge to be able to think critical.
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- Paembonan, Andri Yadi, et al.
(författare)
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An application of LOTEM around salt dome near Houston, Texas
- 2017
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Ingår i: AIP Conference Proceedings. - : American Institute of Physics (AIP). - 0094-243X .- 1551-7616. ; 1861
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Tidskriftsartikel (refereegranskat)abstract
- A salt dome is an important large geologic structure for hydrocarbon exploration. It may seal a porous reservoir of rocks that form petroleum reservoirs. Several techniques such as seismic, gravity, and electromagnetic including magnetotelluric have successfully yielded salt dome interpretation. Seismic has difficulties seeing through the salt because the seismic energy gets trapped by the salt due to its high velocity. Gravity and electromagnetics are more ideal methods. Long Offset Transient Electromagnetic (LOTEM) and Focused Source Electromagnetic (FSEM) were tested over a salt dome near Houston, Texas. LOTEM data were recorded at several stations with varying offset, and the FSEM tests were also made at some receiver locations near a suspected salt overhang. The data were processed using KMS's processing software: First, for assurance, including calibration and header checking; then transmitter and receiver data are merged and microseismic data is separated; Finally, data analysis and processing follows. LOTEM processing leads to inversion or in the FSEM case 3D modeling. Various 3D models verify the sensitivity under the salt dome. In addition, the processing was conducted pre-stack, stack, and post-stack. After pre-stacking, the noise was reduced, but showed the ringing effect due to a low-pass filter. Stacking and post-stacking with applying recursive average could reduce the Gibbs effect and produce smooth data
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- Razumova, Z., et al.
(författare)
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The prognostic role of LRIG proteins in endometrial cancer
- 2019
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Ingår i: International Journal of Gynecological Cancer. - : BMJ Publishing Group Ltd. - 1048-891X .- 1525-1438. ; 29, s. A358-A358
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Introduction/Background Endometrial cancer (EC) is the most common gynaecological malignancy in Sweden. The disease has several prognostic factors. Still, the high amount of EC develops into more aggressive forms of cancer, even though being first considered to be non-aggressive. The LRIG proteins are a family of three integral surface proteins that have a similar domain organisation. The current study evaluated the role of LRIG proteins as prognostic biomarkers in EC.Methodology The cohort included 75 women who underwent a hysterectomy and bilateral salpingo-oophorectomydue to EC at the Department of Women's and Children's Health, Karolinska University Hospital Solna between 2007 and 2012. The expression of LRIG1, LRIG2, and LRIG3 in paraffin biopsies was analysed by immunohistochemistry (IHC) with applying specific polyclonal antibodies. Evaluation of immunostainings was performed by two senior pathologists without knowledge of the disease outcome. The percentage of positive cells was divided in two groups with median percentage as cut off to have two groups of equal size included in the statistical analysis. Then the groups were assessedin connection with different tumour characteristics and clinical outcomes of EC.Results The majority of women in the cohort had >50% LRIG1-, LRIG2-, and LRIG3-positive cells. Among 6047 person-months of follow-up a total, of 14 incident cases of relapsed EC were identified. A statistically significant association between high LRIG3 expression and superior overall survival was observed in the cohort (IRR=2.559, 95 CI=1.054–6.210, p=0.038). LRIG1 and LRIG2 expression did not significantly correlate with survival.Conclusion Our results support the hypothesis that LRIG3 expression may have a prognostic role in women with EC. The significance of LRIG1 and LRIG2 expression remains to be clarified.
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