| 1. |
- Lozano, Rafael, et al.
(författare)
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Measuring progress from 1990 to 2017 and projecting attainment to 2030 of the health-related Sustainable Development Goals for 195 countries and territories: a systematic analysis for the Global Burden of Disease Study 2017
- 2018
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Ingår i: The Lancet. - : Elsevier. - 1474-547X .- 0140-6736. ; 392:10159, s. 2091-2138
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Tidskriftsartikel (refereegranskat)abstract
- Background: Efforts to establish the 2015 baseline and monitor early implementation of the UN Sustainable Development Goals (SDGs) highlight both great potential for and threats to improving health by 2030. To fully deliver on the SDG aim of “leaving no one behind”, it is increasingly important to examine the health-related SDGs beyond national-level estimates. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD 2017), we measured progress on 41 of 52 health-related SDG indicators and estimated the health-related SDG index for 195 countries and territories for the period 1990–2017, projected indicators to 2030, and analysed global attainment. Methods: We measured progress on 41 health-related SDG indicators from 1990 to 2017, an increase of four indicators since GBD 2016 (new indicators were health worker density, sexual violence by non-intimate partners, population census status, and prevalence of physical and sexual violence [reported separately]). We also improved the measurement of several previously reported indicators. We constructed national-level estimates and, for a subset of health-related SDGs, examined indicator-level differences by sex and Socio-demographic Index (SDI) quintile. We also did subnational assessments of performance for selected countries. To construct the health-related SDG index, we transformed the value for each indicator on a scale of 0–100, with 0 as the 2·5th percentile and 100 as the 97·5th percentile of 1000 draws calculated from 1990 to 2030, and took the geometric mean of the scaled indicators by target. To generate projections through 2030, we used a forecasting framework that drew estimates from the broader GBD study and used weighted averages of indicator-specific and country-specific annualised rates of change from 1990 to 2017 to inform future estimates. We assessed attainment of indicators with defined targets in two ways: first, using mean values projected for 2030, and then using the probability of attainment in 2030 calculated from 1000 draws. We also did a global attainment analysis of the feasibility of attaining SDG targets on the basis of past trends. Using 2015 global averages of indicators with defined SDG targets, we calculated the global annualised rates of change required from 2015 to 2030 to meet these targets, and then identified in what percentiles the required global annualised rates of change fell in the distribution of country-level rates of change from 1990 to 2015. We took the mean of these global percentile values across indicators and applied the past rate of change at this mean global percentile to all health-related SDG indicators, irrespective of target definition, to estimate the equivalent 2030 global average value and percentage change from 2015 to 2030 for each indicator. Findings: The global median health-related SDG index in 2017 was 59·4 (IQR 35·4–67·3), ranging from a low of 11·6 (95% uncertainty interval 9·6–14·0) to a high of 84·9 (83·1–86·7). SDG index values in countries assessed at the subnational level varied substantially, particularly in China and India, although scores in Japan and the UK were more homogeneous. Indicators also varied by SDI quintile and sex, with males having worse outcomes than females for non-communicable disease (NCD) mortality, alcohol use, and smoking, among others. Most countries were projected to have a higher health-related SDG index in 2030 than in 2017, while country-level probabilities of attainment by 2030 varied widely by indicator. Under-5 mortality, neonatal mortality, maternal mortality ratio, and malaria indicators had the most countries with at least 95% probability of target attainment. Other indicators, including NCD mortality and suicide mortality, had no countries projected to meet corresponding SDG targets on the basis of projected mean values for 2030 but showed some probability of attainment by 2030. For some indicators, including child malnutrition, several infectious diseases, and most violence measures, the annualised rates of change required to meet SDG targets far exceeded the pace of progress achieved by any country in the recent past. We found that applying the mean global annualised rate of change to indicators without defined targets would equate to about 19% and 22% reductions in global smoking and alcohol consumption, respectively; a 47% decline in adolescent birth rates; and a more than 85% increase in health worker density per 1000 population by 2030. Interpretation: The GBD study offers a unique, robust platform for monitoring the health-related SDGs across demographic and geographic dimensions. Our findings underscore the importance of increased collection and analysis of disaggregated data and highlight where more deliberate design or targeting of interventions could accelerate progress in attaining the SDGs. Current projections show that many health-related SDG indicators, NCDs, NCD-related risks, and violence-related indicators will require a concerted shift away from what might have driven past gains—curative interventions in the case of NCDs—towards multisectoral, prevention-oriented policy action and investments to achieve SDG aims. Notably, several targets, if they are to be met by 2030, demand a pace of progress that no country has achieved in the recent past. The future is fundamentally uncertain, and no model can fully predict what breakthroughs or events might alter the course of the SDGs. What is clear is that our actions—or inaction—today will ultimately dictate how close the world, collectively, can get to leaving no one behind by 2030.
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| 2. |
- Stanaway, Jeffrey D., et al.
(författare)
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Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks for 195 countries and territories, 1990-2017: A systematic analysis for the Global Burden of Disease Study 2017
- 2018
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Ingår i: The Lancet. - 1474-547X .- 0140-6736. ; 392:10159, s. 1923-1994
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Tidskriftsartikel (refereegranskat)abstract
- Background The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 comparative risk assessment (CRA) is a comprehensive approach to risk factor quantification that offers a useful tool for synthesising evidence on risks and risk-outcome associations. With each annual GBD study, we update the GBD CRA to incorporate improved methods, new risks and risk-outcome pairs, and new data on risk exposure levels and risk- outcome associations. Methods We used the CRA framework developed for previous iterations of GBD to estimate levels and trends in exposure, attributable deaths, and attributable disability-adjusted life-years (DALYs), by age group, sex, year, and location for 84 behavioural, environmental and occupational, and metabolic risks or groups of risks from 1990 to 2017. This study included 476 risk-outcome pairs that met the GBD study criteria for convincing or probable evidence of causation. We extracted relative risk and exposure estimates from 46 749 randomised controlled trials, cohort studies, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. Using the counterfactual scenario of theoretical minimum risk exposure level (TMREL), we estimated the portion of deaths and DALYs that could be attributed to a given risk. We explored the relationship between development and risk exposure by modelling the relationship between the Socio-demographic Index (SDI) and risk-weighted exposure prevalence and estimated expected levels of exposure and risk-attributable burden by SDI. Finally, we explored temporal changes in risk-attributable DALYs by decomposing those changes into six main component drivers of change as follows: (1) population growth; (2) changes in population age structures; (3) changes in exposure to environmental and occupational risks; (4) changes in exposure to behavioural risks; (5) changes in exposure to metabolic risks; and (6) changes due to all other factors, approximated as the risk-deleted death and DALY rates, where the risk-deleted rate is the rate that would be observed had we reduced the exposure levels to the TMREL for all risk factors included in GBD 2017.
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| 3. |
- Hoang-Minh, Thao, et al.
(författare)
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Mineralogical Characterization of Di Linh Bentonite, Vietnam: A Methodological Approach of X-ray Diffraction and Transmission Electron Microscopy
- 2014
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Ingår i: Proceedings of 13th International Symposium on Mineral Exploration (ISME-XIII). - Hanoi : Vietnam National University Press, Hanoi. - 9786046215400 ; , s. 143-148
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Konferensbidrag (refereegranskat)abstract
- Vietnam has decided to establish nuclear power as further energy option. In order to develop a Vietnamese reference bentonite as potential barrier in a final repository for high radioactive waste, a detailed mineralogical investigation of Di Linh bentonite (Lam Dong province), lacustrine clay, was carried out by different methods especially transmission electron microscopy (TEM) linked with energy-dispersive X-ray (EDX). From a sample homogenized from 5 tones of the bentonite, mineral formulae of clay particles was calculated The calculation also focuses on randomly interstratifications of two and three members. The fraction <2 μm of Di Linh bentonite is composed mainly by montmorillonite (Ca0.06Mg0.03Na0.09K0.03Al1.39Fe0.25Mg0.26(OH)2 Si3.96Al0.04O10) and regular ordering (R1) illite-smectite interstratifications with K- and charge-deficiency (Ca0.04Mg0.07Na0.18K0.16Al1.76Fe0.08Mg0.16(OH)2Si3.62Al0.38O10). Additionally, Fe-poor kaolinite-smectite-vermiculite interstratifications and trace of Fe-rich chloritesmectite- vermiculite interstatifications were identified. TEM-investigations showed analytical proofs of the sedimentary character of smectite formation in the Di Linh deposit. Parent muscovite was weathered in several steps in two different environments: (i) K-leaching and layer-wise alteration into kaolinite; (ii) further edge- controlled alteration of mica into lathlike montmorillonite particles under dissolution of kaolinite layers from former kaolinite-mica intergrowths. Mineralogical composition of the Di Linh bentonite with mainly montmorillonite and illite-rich illite-smectite interstratifications shows that the Di Linh bentonite can be a suitable barrier candidate in final repositories.
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| 4. |
- Hoang-Minh, Thao, et al.
(författare)
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Use of TEM-EDX for structural formula identification of clay minerals : a case study of Di Linh bentonite, Vietnam
- 2019
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Ingår i: Journal of applied crystallography. - : International Union of Crystallography (IUCr). - 0021-8898 .- 1600-5767. ; 52:1, s. 133-147
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Tidskriftsartikel (refereegranskat)abstract
- Transmission electron microscopy linked with energy-dispersive X-ray spectroscopy (TEM-EDX) was applied to characterize mineralogical signals ofweathering processes in the Di Linh bentonite deposit (Vietnam) and to visualize the effects of Na activation on the smectitic phases. Modelling of X ray diffraction patterns (oriented mount) was applied in order to refine the computed structural formula. X-ray diffraction, X-ray fluorescence and Fouriertransform infrared spectroscopy (FT-IR) methods were also applied to verify the TEM-EDX results. An Excel-based routine has been developed in this research to allow fast computation of structural formulae and classification of the investigated clay particles. This routine supports the acquirement of 100 300 TEM-EDX analyses as a representative set of individual particles for each sample. The Excel-based routine involves end members of different clay mineral groups and interstratifications with two or three members (e.g. illite smectite interstratifications – IS-ml; dioctahedral vermiculite–smectite interstratifications – diVS-ml; and kaolinite–montmorillonite–dioctahedral vermiculite interstratifications – KSV-ml). The routine is now freely available. According to the identification procedure, the <2 mm fraction of the Di Linh bentonite (Vietnam) is composed mainly of K- and charge-deficient illite smectite interstratifications (or diVS-ml): montmorillonite-rich randomly ordered (R0) type and illite-rich regularly ordered (R1) type. Additionally, Fe-poor KSV-ml was identified.Industrial Na activation of the Di Linh bentonite resulted in an increase of theR1 diVS-ml portion and dissolution of a large part of the smectite-rich phases.The TEM-EDX approach also gave analytical proof of a sedimentary processfor Di Linh smectite. The parent muscovite was altered in two different environments: (i) K-leaching and layer-wise alteration into kaolinite (weathering), and (ii) further edge-controlled alteration of mica into lath-like montmorillonite particles associated with a dissolution of kaolinite layers from the former kaolinite–mica intergrowths by heat impact (basalt flow).
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| 5. |
- Berg, Håkan, et al.
(författare)
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An ecological economic comparison between integrated rice-fish farming and rice monocultures with low and high dikes in the Mekong Delta, Vietnam
- 2023
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Ingår i: Ambio. - 0044-7447 .- 1654-7209. ; 52:9, s. 1462-1474
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Tidskriftsartikel (refereegranskat)abstract
- This study makes an ecological economic comparison between three different rice farming strategies in the Mekong Delta. Interviews were made with 30 farmers with two crops of rice and low dikes (2RLd), 30 farmers with three crops of rice and high dikes (3RHd) and 18 farmers with two crops of rice and one crop of fish (2RF). 2RF farmers had the highest annual net income and benefit cost ratio, because of low production costs and high yields of rice and fish. 2RLd farmers had the lowest annual net income. 3RHd had the highest annual rice yield, but also used the highest amount of rice seeds and agrochemicals, generating the lowest benefit cost ratio. Most farmers (70%) preferred two crops because of a higher production efficiency. High dikes and frequent use of pesticides and fertilizers were seen to decrease the water and rice quality, connectivity and biodiversity in farms with three crops. It is concluded that rice farming with two crops, and especially if integrated with fish and applying IPM, provides a sustainable alternative to rice farming with three crops and high dikes, because it makes use of the high connectivity within the rice-field ecosystem for an efficient production of healthy food through increased recycling of nutrients and natural pest control mechanisms.
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| 6. |
- Nguyen, Hong Hanh, et al.
(författare)
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"I can make more from selling medicine when breaking the rules" : understanding the antibiotic supply network in a rural community in Viet Nam
- 2019
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Ingår i: BMC Public Health. - : BioMed Central. - 1471-2458. ; 19:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: As in many other low and middle income countries (LIMCs), Vietnam has experienced a major growth in the pharmaceutical industry, with large numbers of pharmacies and drug stores, and increasing drug expenditure per capita over the past decade. Despite regulatory frameworks that have been introduced to control the dispensing and use of prescription-only drugs, including antibiotics, compliance has been reported to be strikingly low particularly in rural parts of Vietnam. This qualitative study aimed to understand antibiotic access and use practices in the community from both supplier and consumer perspectives in order to support the identification and development of future interventions.METHODS: This qualitative study was part of a project on community antibiotic access and use (ABACUS) in six LMICs. The focus was Ba Vi district of Hanoi capital city, where we conducted 16 indepth interviews (IDIs) with drug suppliers, and 16 IDIs and 6 focus group discussions (FGDs) with community members. Drug suppliers were sampled based on mapping of all informal and formal antibiotic purchase or dispensing points in the study area. Community members were identified through local networks and relationships with the field collaborators. All IDIs and FGDs were audio-taped, transcribed and analysed using content analysis.RESULTS: We identified a large number of antibiotic suppliers in the locality with widespread infringements of regulatory requirements. Established reciprocal relationships between suppliers and consumers in drug transactions were noted, as was the consumers' trust in the knowledge and services provided by the suppliers. In addition, antibiotic use has become a habitual choice in most illness conditions, driven by both suppliers and consumers.CONCLUSIONS: This study presents an analysis of the practices of antibiotic access and use in a rural Vietnamese setting. It highlights the interactions between antibiotic suppliers and consumers in the community and identifies possible targets for interventions.
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| 7. |
- Quang-Thuy, Ha, et al.
(författare)
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A Bisimulation-based Method of Concept Learning for Knowledge Bases in Description Logics
- 2012
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Ingår i: SoICT 2012 - 3rd International Symposium on Information and Communication Technology. - New York, New York, USA : ACM Press. ; , s. 241-249
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Konferensbidrag (refereegranskat)abstract
- We develop the first bisimulation-based method of concept learning, called BBCL, for knowledge bases in description logics (DLs). Our method is formulated for a large class of useful DLs, with well-known DLs like ALC, SHIQ, SHOIQ, SROIQ. As bisimulation is the notion for characterizing indis-cernibility of objects in DLs, our method is natural and very promising.
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| 8. |
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| 9. |
- Berg, Håkan, et al.
(författare)
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Stakeholders assessment of status and trends of ecosystem services in the Mekong Delta for improved management of multifunctional wetlands
- 2023
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Ingår i: Journal of Environmental Management. - 0301-4797 .- 1095-8630. ; 338
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Tidskriftsartikel (refereegranskat)abstract
- Increased agriculture and aquaculture production in the Mekong Delta during the last two decades has improved farmers' income, national export earnings and reduced poverty, but has also impacted on the environment and ecosystem services (ES) of importance to peoples' livelihoods and well-being. Through group discussions, interviews and questionnaires, this study assesses stakeholders’ perceptions of the status and trends of ES in the Mekong Delta and how these have been influenced by agriculture development. 15 of 24 ES were assessed to be impacted negatively by agriculture intensification, and especially supporting and regulating ES (SRES). Only a few provisioning ES (PrES), related to farming, were assessed to be in a good and stable supply, because of human interventions to create favorable conditions for these ES. Among the ten highest ranked ES, eight belonged to PrES and two belonged to SRES. There was a positive correlation between rank and awareness of ES. The supply of most SRES was perceived to be in a low and declining status and assessed to be in a high need for improved management. Some ES, such as pest-control had been complemented with human-made substitutes, such as pesticides, which however sometimes weakened rather than strengthened the ES. Cultural ES (CES) were often ranked lower and of less management concern than the other groups of ES. It is concluded that future agriculture strategies need a more balanced management of ES for a long-term production of healthy food and increased resilience of the Mekong Delta to cope with future challenges, such as climate change and upstream dams.
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| 10. |
- Bergström, Anna, 1983-, et al.
(författare)
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A facilitated social innovation : stakeholder groups using Plan-Do-Study-Act cycles for perinatal health across levels of the health system in Cao Bang province, Vietnam
- 2023
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Ingår i: Implementation Science Communications. - : BioMed Central (BMC). - 2662-2211. ; 4:1
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundUniversal coverage of evidence-based interventions for perinatal health, often part of evidence-based guidelines, could prevent most perinatal deaths, particularly if entire communities were engaged in the implementation. Social innovations may provide creative solutions to the implementation of evidence-based guidelines, but successful use of social innovations relies on the engagement of communities and health system actors. This proof-of-concept study aimed to assess whether an earlier successful social innovation for improved neonatal survival that employed regular facilitated Plan-Do-Study-Act meetings on the commune level was feasible and acceptable when implemented on multiple levels of the health system (52 health units) and resulted in actions with plausibly favourable effects on perinatal health and survival in Cao Bang province, northern Vietnam.MethodsThe Integrated Promoting Action on Research Implementation in Health Services (i-PARIHS) framework guided the implementation and evaluation of the Perinatal Knowledge-Into-Practice (PeriKIP) project. Data collection included facilitators’ diaries, health workers’ knowledge on perinatal care, structured observations of antenatal care, focus group discussions with facilitators, their mentors and representatives of different actors of the initiated stakeholder groups and an individual interview with the Reproductive Health Centre director. Clinical experts assessed the relevance of the identified problems and actions taken based on facilitators’ diaries. Descriptive statistics included proportions, means, and t-tests for the knowledge assessment and observations. Qualitative data were analysed by content analysis.ResultsThe social innovation resulted in the identification of about 500 relevant problems. Also, 75% of planned actions to overcome prioritised problems were undertaken, results presented and a plan for new actions to achieve the group’s goals to enhance perinatal health. The facilitators had significant roles, ensuring that the stakeholder groups were established based on principles of mutual respect. Overall, the knowledge of perinatal health and performance of antenatal care improved over the intervention period.ConclusionsThe establishment of facilitated local stakeholder groups can remedy the need for tailored interventions and grassroots involvement in perinatal health and provide a scalable structure for focused efforts to reduce preventable deaths and promote health and well-being.
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| 11. |
- Kasbohm, Jörn, et al.
(författare)
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Lab-scale performance of selected expandable clays under HLW repository conditions
- 2013
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Ingår i: Environmental Earth Sciences. - : Springer Science and Business Media LLC. - 1866-6280 .- 1866-6299. ; 69:8, s. 2569-2579
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Tidskriftsartikel (refereegranskat)abstract
- Smectite clay has been proposed for embedding canisters with highly radioactive waste in deep repositories because of its isolating capacity. Montmorillonite-rich bentonite is a premier buffer candidate for many national organizations that are responsible for disposal of such waste. Experience from the use of drilling mud at large depths indicates that other smectite clay minerals are more stable chemically and saponite is one of them. The physical properties of smectitic mixed-layer minerals like Friedland clay are known to be less sensitive to high salt contents and such clay may also be a buffer candidate. Montmorillonite-rich MX-80 clay, Greek saponite with a minor amount of palygorskite, and Friedland clay were investigated in hydrothermal tests with dense samples confined in oedometers with 95 °C temperature at one end, which was made of copper, and 35 °C at the other, for 8 weeks. A 1 % CaCl 2 solution was circulated through a filter at the cold end. At the end of the tests, the samples were sliced into three parts, which were tested with respect to expandability, hydraulic conductivity, and chemical composition. The tests showed that while the saponite was hardly changed at all and did not take up any copper, MX-80 underwent substantial changes in physical performance and adsorbed significant amounts of copper. The Friedland clay sample was intermediate in both respects
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| 12. |
- Pusch, Roland, et al.
(författare)
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Deep disposal of spent nuclear fuel
- 2019
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Ingår i: Waste Management and the Environment IX. - : WIT Press. ; , s. 399-414
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Konferensbidrag (refereegranskat)abstract
- An alternative but still untested approach is to dispose of highly radioactive waste in very deep boreholes, a concept being considered in the UK and the US. One version of this concept known as Very-Deep-Hole (VDH) storage proposes drilling of up to 4 km deep holes and placing in a series of stacked super-containers sealed by a combination of dense clay and concrete. In this case the risk of losing clay material by dispersion and erosion where the holes intersect fracture zones would be eliminated by casting concrete of a new type. VDH containment relies on the use of copper or Navy Bronze tubes filled with dense clay in the upper parts of the holes and with clay-embedded canisters with waste in the lower parts. The maturation and isolating function of the clay seals in the holes and their chemical interaction with concrete and waste canisters are considered and assessed. The work has focused on the mechanical testing and microscope investigations of the clay/concrete. Hydrothermally treated clay and concrete, exposed to 20-150°C, which represents the conditions over the entire length of a real VDH, have been tested. The recorded impact of strong heating showed stiffening and some reduction in hydraulic conductivity of the clay and concrete.
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| 13. |
- Pusch, Roland, et al.
(författare)
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Disposal of Low- and Intermediate-Level Radioactive Waste
- 2019
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Ingår i: Journal of Earth Sciences and Geotechnical Engineering. - UK : Scientific Press International Limited. - 1792-9040 .- 1792-9660. ; 9:3, s. 237-272
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Tidskriftsartikel (refereegranskat)abstract
- As for isolation of high-level radioactive waste by use of smectite clay it serves very well also for hindering radionuclides from low- and intermediate-level waste to contaminate groundwater. It can be used for minimizing groundwater flow through and along waste packages and for providing them with ductile embedment for eliminating the risk of damage caused by displacements in host rock or concrete vaults. The clay can have the form of liners placed and compacted on site over vaults constructed on the ground surface, or consist of compacted blocks of clay granules that are tightly placed around waste packages in underground drifts and rooms. In either case the initially incompletely water saturated clay will swell in conjunction with water uptake until tight contact with the confining medium has been established. The clay seals must be sufficiently dense to fulfill criteria set with respect to hydraulic conductivity and swelling capacity, paying due attention to the salt content in the porewater. Their physical and chemical stabilities must be acceptable in short- and long-term perspectives, which is a few hundred years for most low-level wastes up to tens of thousands of years for long-lived waste.
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| 14. |
- Pusch, Roland, et al.
(författare)
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Holmehus clay — A Tertiary smectitic clay of potential use for isolation of hazardous waste
- 2015
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Ingår i: Engineering Geology. - : Elsevier BV. - 0013-7952 .- 1872-6917. ; 188, s. 38-47
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Tidskriftsartikel (refereegranskat)abstract
- The Danish Tertiary Holmehus clay belongs to the series of illite-smectite mixed-layer clays in northern Europe and has a potential to serve as an effective engineered barrier for isolating hazardous waste. Mineralogical specification was made of the components illite/smectite mixed-layer and dioctahedral vermiculite/smectite mixed-layer structures. The lower content of expandable phase than of smectite- rich clays like MX-80 gives somewhat higher hydraulic conductivity and somewhat lower swelling pressure but both are deemed suitable for isolating canisters with high-level radioactive waste in deeprepositories for densities at water saturation of at least 1900 kg/m3. The lower swelling pressure, the potential of being chemically more stable, and the high buffer capacity by providing dissolved Si makes Holmehus clay a candidate for use in both deep and near-surface repositories.
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| 15. |
- Pusch, Roland, et al.
(författare)
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Mechanisms Involved in Maturation of Clay Seals in Boreholes for Storing Spent Reactor Fuel
- 2019
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Ingår i: Journal of Earth Sciences and Geotechnical Engineering. - UK : Scientific Press International Limited. - 1792-9040 .- 1792-9660. ; 9:3, s. 197-226
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Tidskriftsartikel (refereegranskat)abstract
- Smectite clay, especially montmorillonite, is proposed for isolating canisters containing highly radioactive waste (HLW) like spent reactor fuel placed in deep boreholes. It is used for minimizing groundwater flow around and along waste packages (“Buffer Clay”) and for providing them with ductile embedment for eliminating risk of canister damage caused by displacements in the host rock. The clay has the form of heavily compacted blocks of granules that swell in conjunction with water uptake until their full hydration potential has been utilized. The dense clay blocks are fitted in perforated supercontainers that are submerged in smectite mud. The long-term chemical stability of the clay is sufficient for providing the required waste-isolating capacity, which is primarily supplied by the heavyness of stagnant, very salt groundwater at depth.
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| 16. |
- Pusch, Roland, et al.
(författare)
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The role of smectite clay barriers for isolating high-level radioactive waste (HLW) in shallow and deep repositories
- 2015
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Ingår i: Procedia Earth and Planetary Science. - : Elsevier. - 1878-5220. ; 15, s. 680-687
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Tidskriftsartikel (refereegranskat)abstract
- The major engineered barriers to migration of radionuclides from HLW in repositories are the canister and surrounding smectite clay. They interact physically and chemically by which the properties of both are changed, especially of the smectite “buffer” clay that is examined in the paper. The canisters are made of copper-lined iron according to the Swedish and Finnish concepts, steel being an alternative. The function of the host rock is of importance and the paper examines the role of two repository concepts with long subhorizontal or deep vertical holes for placing the waste. The hydraulic conductivity of the canister-embedding smectite clay can be significantly raised by high temperature and temperature gradients, which generate precipitation of salt and silica in different parts of the buffer clay. The impact of the degrading processes on the waste-isolating capacity is different for shallow repositories in permeable rock and for very deep disposal with higher temperature. The latter has stagnant groundwater as major barrier to the migration of radionuclides.
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| 17. |
- Son, Vi Thanh, et al.
(författare)
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Teaching English for young language learners at Grade 5: Teachers' beliefs in two contrasting national approaches compared, and pedagogical implications
- 2019
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Ingår i: OpenTESOL-Proceedings of the 7th OpenTESOL intrenational conference 2019 : Innovation and inspiration: Building the future of language education - Innovation and inspiration: Building the future of language education. ; , s. 423-442
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Konferensbidrag (refereegranskat)abstract
- The aim of the paper was to investigate EFL (English as a foreign language) primary school teachers’ beliefs regarding their teaching methods used in English at grade 5 in the classroom, which was a part of my PhD research (Son, 2018). Interviews (teachers at Grade 5 observed classes; Responses N=2, Sweden and N=3, Vietnam) and questionnaires to English teachers at grade 5 in Swedish and Vietnamese primary schools (additional teachers at Grade 5; Responses N=10, Sweden and N=52, Vietnam) were used. The content of the questionnaire was based on the COLT observation scheme (Spada & Fröhlich, 1995) and adapted to be suitable to the study (Son, 2018) of teaching methods at Grade 5. The teachers’ answers showed the major different degree of focusing on communication and grammar in teaching English classes at primary level between the groups, in spite of some similarities regarding classroom activities (group work), source of material and the languages used in the classroom. The results not only casted light on teachers’ beliefs in two contrasting national approaches in their English teaching methods for young language learners but also led the author to discuss further pedagogical implications
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