| 1. |
- Antonsson, Helena, 1962-
(författare)
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Interaktion i särskilt boende för personer med utvecklingsstörning och utmanande beteende
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Bakgrund: Många personer med utvecklingsstörning har kommunikativa svårigheter och har därför behov av att utveckla olika sätt att kommunicera för att kunna förstå andra och göra sig förstådda. Svårigheter i kommunikationen påverkar interaktionen mellan personer med utvecklingsstörning och deras vårdare. Detta ställer höga krav på vårdare att kunna tolka och förstå den enskilda individens sätt att uttrycka önskningar och behov. På samma sätt riskerar vårdares budskap att missförstås. Om vårdaren misslyckas att förstå den boendes kommunikation och vice versa, kan det leda till situationer med utmanande beteende exempelvis i form av vägran, verbal eller fysisk aggressivitet.Syfte: Det övergripande syftet med avhandlingen är att studera interaktion mellan vuxna personer med utvecklingsstörning och vårdare i gruppbostäder, samt att studera effekter av en utbildningsintervention för vårdare som arbetar i gruppbostäder.Metod: Avhandlingens samtliga delstudier har genomförts i gruppbostäder för personer med utvecklingsstörning bland boende och vårdare i ett län i norra Sverige. I studie I insamlades data kring 556 personer med utvecklingsstörning. I studie II och III deltog 16 vårdare och 11 personer med utvecklingsstörning. I studie IV deltog 7 vårdare. Studie I bygger på personalens skattningar av funktionsnivåer och förekomst av begränsningsåtgärder. I Studie II och III utgörs data av videoobservationer och narrativa intervjuer. I studie IV användes flera datainsamlingsmetoder i en mixed method design med både vårdarnas skattningar, med hjälp av instrument och semi-strukturerade intervjuer. Analys av materialet i studie II, III och IV har gjorts med kvalitativ innehållsanalys och i studie I och IV har data analyserats statistiskt.Resultat: I studie I framkom att av 556 boende hade 99 (18%) varit föremål för fysiska begränsningsåtgärder under den senaste veckan. Av dessa 99 hade nästan alla varit föremål för mer än en typ av begränsningsåtgärd. Den vanligaste begränsningsåtgärden var bälte i stol (74%). Användningen av begränsningsåtgärder var relaterade både till fysiska funktionsnedsättningar och till beteende.I studie II reflekterade vårdare över videoinspelad interaktion där vårdarna medverkat, både framgångsrik och misslyckad interaktion. Exempel på framgångsrik interaktion var att förstå tecken, kunna möta behov och hantera situationer med utmanande beteenden. Vårdarna reflekterade över att framgångsrik interaktion ledde till säkerhet, trygghet och självförtroende hos de boende. Vårdarna reflekterade även över de konsekvenser misslyckad interaktion fick i form av irritation, aggression och våld från de boende.I studie III studerades videoinspelad interaktion mellan 11 personer med utvecklingsstörning och 16 av deras vårdare. Verbal och icke-verbal interaktion identifierades. Fyra inspelade situationer valdes ut för att belysa framgångsrikt samspel. Resultatet visade att framgångsrikt samspel mellan personer med utvecklingsstörning och deras vårdare bland annat bygger på möjligheten att bekräfta varandra, dela vardagshändelser, ge tid och utrymme och på att använda ett kongruent och tydligt språk.I studie IV utvärderades effekterna av en web-baserad utbildningsintervention, vars syfte var att förbättra interaktionen mellan personer med utvecklingsstörning och vårdare samt att därmed reducera förekomsten av situationer med utmanande beteende. Resultatet visade att vårdarna hade förbättrat sin förmåga att hantera situationer med utmanande beteende och att förekomsten av utmanande beteende minskat. Vårdarna beskrev att den web-baserade utbildningen upplevts givande och möjlig att ta del av parallellt med arbetet.Slutsats: Fysiska begränsningsåtgärder förekommer i gruppbostäder för personer med utvecklingsstörning. Användningen av begränsningsåtgärder kan vara relaterade både till fysiska funktionsnedsättningar och till beteenden i samspelet mellan brukare och vårdare. Vårdare upplever användningen av fysiska begränsningsåtgärder svår och tröttande. Brott i kommunikationen mellan personer med utvecklingsstörning och deras vårdare kan leda till försvårad interaktion med risk för situationer med utmanande beteenden. När vårdare är framgångsrika i interaktionen med personer med utvecklingsstörning ger det tillfredsställelse både för de boende och vårdarna. Vårdarna upplever dock ofta hjälplöshet och osäkerhet i relation till hantering av situationer med utmanande beteende och efterfrågar utbildning. Web-baserad utbildning om interaktion med personer med utvecklingsstörning och utmanande beteende har i vår studie visat sig ge lovande effekter och bör vara möjlig att utveckla för både introduktion av nyanställda vårdare och för kompetensutveckling bland mer erfaren personal.
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| 2. |
- Augustsson, Anna, et al.
(författare)
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Failure of generic risk assessment model framework to predict groundwater pollution risk at hundreds of metal contaminated sites : Implications for research needs
- 2020
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Ingår i: Environmental Research. - : Elsevier. - 0013-9351 .- 1096-0953. ; 185, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- Soil pollution constitutes one of the major threats to public health, where spreading to groundwater is one of several critical aspects. In most internationally adopted frameworks for routine risk assessments of contaminated land, generic models and soil guideline values are cornerstones. In order to protect the groundwater at contaminated sites, a common practice worldwide today is to depart from health risk-based limit concentrations for groundwater, and use generic soil-to-groundwater spreading models to back-calculate corresponding equilibrium levels (concentration limits) in soil, which must not be exceeded at the site. This study presents an extensive survey of how actual soil and groundwater concentrations, compiled for all high-priority contaminated sites in Sweden, relate to the national model for risk management of contaminated sites, with focus on As, Cu, Pb and Zn. Results show that soil metal concentrations, as well as total amounts, constitute a poor basis for assessing groundwater contamination status. The evaluated model was essentially incapable of predicting groundwater contamination (i.e. concentrations above limit values) based on soil data, and erred on the "unsafe side" in a significant number of cases, with modelled correlations not being conservative enough. Further, the risk of groundwater contamination was almost entirely independent of industry type. In essence, since neither soil contaminant loads nor industry type is conclusive, there is a need for a supportive framework for assessing metal spreading to groundwater accounting for site-specific, geochemical conditions.
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| 3. |
- Lundström, Mats, 1956-
(författare)
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Våld - utmaning och utmattning : vårdares utsatthet och upplevelser i samband med våld i gruppbostäder för personer med utvecklingsstörning
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- ABSTRACT This thesis aims to explore the prevalence of violence towards caregivers working in group home for people with learning disabilities, as well as the influence of work climate and personality on the caregivers’ experiences of strain and exposure to violence. The thesis comprises four studies conducted among caregivers working in group homes for people with learning disabilities in one urban district in Sweden. Study I includes data regarding caregivers’ exposure to violence and their demographics. In study II and III data were collected by instruments for measuring caregivers’ personalities and experiences of the work climate as well as emotional reactions, strain, and experiences of burnout. Data were also collected by 50 narrative interviews with 44 caregivers reporting exposure to violence. In order to illuminate caregivers’ experiences of being exposed to violence, the interviews were transcribed and interpreted using qualitative content analysis. The results showed that 31% of the caregivers (n=120) had been exposed to violence during the preceding year, with physical violence being the most common type. Weak relationships were found between reported exposure to violence and caregivers’ age and education (I). Among those in studies II and III who completed all instruments (n=112), 45 caregivers (40%) reported exposure to violence. A significant difference in age was found between exposed and not exposed caregivers. In the total sample of studies II and III, 30% (n=41) of the caregivers were at risk of developing burnout. The relationship between exposure to violence and the caregivers’ experiences of the work climate (CCQ) showed that “debates” was the only factor that on average was significantly higher among caregivers reporting violence from the residents. The caregivers’ emotional reactions, strain, and work climate factors explained 35% of the variance in burnout scores (II). No significant relationships were found between the caregivers’ personalities (TCI and RSES) and their exposure to violence. Personality dimensions explained 32% of the variance of the caregivers’ experiences of burnout. The results did not show a significant relationship between a caregiver’s personality and exposure to violence. However, those exposed to violence reported more emotional exhaustion than those not exposed (III). Caregivers exposed to violence reported feelings of powerlessness, insufficiency, anger and violence was very seldom followed by support from the managers at the group homes (I). Interviews show that caregivers’ experiences are about “falling apart” and “keeping it together”. Falling apart involves fear, powerlessness, sadness, anger, and timelessness, while keeping it together involves joy, respect, self-reflection, and habituation. Destructive experiences are balanced by a more constructive view of the situation by keeping the situation, and the caregivers themselves, together. The findings show that exposure to violence occurs frequently and a large proportion of the exposed caregivers are at risk for burnout. It was not possible to confirm the relationships between the caregivers’ personality, experiences of the work climate, and exposure to violence but partly to emotional reactions, strain and burnout. The findings of the four studies are discussed in relation to how it is to live and work in an environment where violence is of frequent occurrence.
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| 4. |
- Uddh Söderberg, Terese, 1976-, et al.
(författare)
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Challenges in geochemical modelling of metal(loid) solubility and binding mechanisms along a soil profile at a multi-contaminated site
- 2024
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Ingår i: Applied Geochemistry. - : Elsevier. - 0883-2927 .- 1872-9134. ; 170
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Tidskriftsartikel (refereegranskat)abstract
- Recognising the need for robust models in predicting groundwater contamination risks from metal(loid)s in contaminated topsoil, this study focuses on the geochemical behaviour of As, Cd, Cu, Pb, Sb and Zn in one of Sweden’s most heavily contaminated areas. Samples were collected from the waste zone and underlying subsoil down to 5 meters and batch experiments were carried out to assess pH-dependent solubility. The results indicate that Cd, Cu, Pb and Zn are efficiently immobilized in the waste zone, while As(V) and Sb(V) are more easily leached. With the exception of Pb and Cu at high pH, the mobilized metals appear to be predominantly in a truly dissolved state, as confirmed by ultrafiltration at 10 kDa.Speciation modelling using Visual MINTEQ did not suggest a significant role of precipitates such as Zn or Pb arsenates and phosphates, although their involvement could not be ruled out. To better understand sorption/desorption patterns, a multi-surface geochemical model was established, drawing on the Stockholm Humic and CD-MUSIC models for organic matter and Fe/Al (hydr)oxide sorption. However, when default parameters were used, the model consistently overestimated the solubility of Cd, Cu, Pb and Zn in both the waste zone and the uncontaminated subsoil. In contrast, As(V) solubility was generally underestimated, also when the reactive surface area of the Fe- and Al (hydr)oxides was decreased in the model. The model's performance was better for Sb(V), though not without imperfections. When the parameters for organic matter were adjusted such that 100% of the solid-phase organic matter was active with respect to ion binding, but only 25% of the dissolved organic matter, the model description improved considerably for Pb and Cu in the upper soil layers. The model revealed distinct differences in the adsorption behaviour of the metal cations, with Pb being sorbed mostly to Fe/Al (hydroxides), whereas a considerable part of Cu was sorbed to organic matter, particularly in the waste zone.Possibly, the dissolution of easily weatherable metal-containing mineral phases may have contributed to the poor model performance for Cd, Zn and for Cu in the deeper soil layers, although other factors, such as a contribution of hydrous SiO2 or Mn oxides to metal binding, could not be ruled out. Metal sorption to carbonate phases may also have been a contributing factor in the waste zone. Lastly, the reactivity of Fe- and Al (hydr)oxides may have been overestimated by oxalate extraction when default parameters for high-surface-area ferrihydrite were applied. These findings provide valuable insights for environmental management and underscore the need for a more detailed characterization of metal(loid) sorption in contaminated soils, as well as the development of improved modelling strategies to enhance solubility predictions.
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| 5. |
- Uddh Söderberg, Terese, 1976-, et al.
(författare)
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Heavy metal transport at a contaminated glassworks site in southeast Sweden.
- 2016
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Heavy metal transport at a contaminated glassworks site in southeast Sweden.In the “Kingdom of crystal” in southeastern Sweden there are a large number of glassworks sites, which are characterized by high pollution levels of a number of metal contaminants. At Pukeberg glassworks site, which is the focus of this study, As, Ba, Cd, Pb, Sb and Zn are present in significantly elevated levels. For this study, which aim is to characterize the release of metals from the glass waste into soil water and groundwater, 54 soil samples from both saturated and unsaturated zone were gathered. Soil water were sampled from lysimeters installed on the landfill area and groundwater were collected from sampling tubes located upstream, at and downstream of the landfill area. The collected samples were analyzed and distribution coefficients (Kd) were calculated as the ratio of the average pseudo-total metal concentrations in soil (from the landfill site with visible glass) to the average dissolved metal concentrations in soil water to describe the leachability of the metal(loid) in the wastes.High concentrations of metal(loid)s were found in soil water samples at the landfill (collected at 30 and 60 cm depth), indicating that metals are leached from the solid waste materials. The distribution coefficients indicate the highest leachability for Ba (Kd= 150 l/kg) and Sb (Kd= 190 l/kg), a moderately leachability for Cd (Kd= 860 l/kg) and Zn (Kd= 500) and the lowest leachability for As and Pb (Kd= 6000 and 16000 respectively). Examining the soil profiles shows that the metal concentrations are considerable lower when there are no visible glass wastes in the soil, which implies that the majority of leached metals are retained in the waste pile. Significant sorption is also suggested by the low concentrations measured in the groundwater samples. The theoretical dilution of the catchment area alone, cannot explain the decrease in metal concentration between the soil water and the groundwater. With exception for Sb, that seems to move relatively unrestrained from the unsaturated zone to the saturated zone.The results indicate that there are sorption processes involved, preventing or slowing down the transport of the investigated metals through the unsaturated zone. The responsible geochemical processes need to be established before assessing remediation strategies for the contaminated area, as it gives information on the factors controlling the metal leaching.
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| 6. |
- Uddh Söderberg, Terese, 1976-, et al.
(författare)
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Metal solubility and transport at a contaminated landfill site – From the source zone into the groundwater
- 2019
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Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 668, s. 1064-1076
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Tidskriftsartikel (refereegranskat)abstract
- Risks associated with metal contaminated sites are tightly linked to material leachability and contaminant mobility. In this study, metal solubility and transport were characterized within a glass waste landfill through i) lysimeter-collection of pore water and standardized batch leaching tests, ii) soil profiles extending from the landfill surface, through unsaturated soil underneath, and into the groundwater zone, and iii) groundwater samples upstream, at, and downstream of the landfill. The soil analyzes targeted both pseudo-total and geochemically active concentrations of contaminant metals (As, Cd, Pb, Sb) and basic soil geochemistry (pH, org. C, Fe,Mn). Water samples were analyzed for dissolved, colloid-bound and particulate metals, and speciation modelling of the aqueous phase was conducted. The results revealed a highly contaminated system, with mean metal concentrationsin the waste zone between 90 and 250 times the regional background levels. Despite severe contamination of the waste zone and high geochemically active fractions (80–100%) of all contaminant metals as well as elevated concentrations in landfill pore water, the concentrations of Cd and Pb decrease abruptly at the transition between landfill and underlying natural soil and no indication of groundwater contamination was found. The efficient cation retention is likely due to the high pH. However, the sorption of As and Sb is weaker at such high pH,which explains their higher mobility from the pore water zone into groundwater. The field soil:solution for Pb, ranging from 140 to 2,900,000 l kg−1), despite little variability in basic geochemical variables, which we suggest is due to waste material heterogeneity.
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| 7. |
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| 8. |
- Alakangas, Linda J., et al.
(författare)
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Diverse fractionation patterns of Rare Earth Elements in deep fracture groundwater in the Baltic Shield - Progress from utilisation of Diffusive Gradients in Thin-films (DGT) at the Aspo Hard Rock Laboratory
- 2020
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Ingår i: Geochimica et Cosmochimica Acta. - : Elsevier. - 0016-7037 .- 1872-9533. ; 269, s. 15-38
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Tidskriftsartikel (refereegranskat)abstract
- Rare earth elements (REEs) were studied in groundwater in fractures at depths between 144 m and 450 m in Proterozoic granitoids on the Baltic Shield at a coastal site in south eastern Sweden (Aspo Hard Rock Laboratory). A specially designed device was used to sample the groundwater under in situ high pressure and low redox conditions. The REEs were measured via both diffusive gradients in thin-films (DGT) samplers after approximately three-week deployment times, and after conventional filtration (0.45 mu m membrane filters). The concentrations of REEDGT were lower than the REE0.45 mu m concentrations in all 14 studied groundwaters. This is explained by development of a diffuse boundary layer (DBL) in the solution at the DGTs caused by the low flow, and in some of the groundwaters additionally by the presence of organically complexed REE that diffuse slowly in the diffusive gel of the DGT. Among the 14 studied groundwaters there was a huge range in REEDGT-fractionation patterns, ranging from enrichment to a nearly three-order-of-magnitude depletion of the heavy REEs (HREEs), despite a relatively homogenous bedrock (granitoids). The HREE enrichment is explained by preservation of the fractionation signature as HREE enriched sea water intruded and flowed through the fractures, supported by the high proportion of modelled REE fulvic-acid complexes in these waters. The strong HREE depletion, which occurred in saline groundwater, was ascribed to an advanced REE equilibrium between the groundwater and primary and/or secondary minerals and the pore water in the bedrock. Yet other groundwaters had flat or moderately HREE depleted patterns, which in some cases may have been caused by mixing of small portions of surficial waters with saline groundwater. (C) 2019 Elsevier Ltd. All rights reserved.
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| 9. |
- Alakangas, Linda J., et al.
(författare)
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Sampling and Characterizing Rare Earth Elements in Groundwater in Deep-Lying Fractures in Granitoids Under In Situ High-Pressure and Low-Redox Conditions
- 2014
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Ingår i: Aquatic geochemistry. - : Springer Science and Business Media LLC. - 1380-6165 .- 1573-1421. ; 20:4, s. 405-418
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Tidskriftsartikel (refereegranskat)abstract
- Several countries are preparing to dispose of radioactive nuclear waste deep underground in crystalline rock. This type of bedrock is commonly extensively fractured and consequently carries groundwater that serves as a medium for transporting metals and radionuclides. A group of metals of particular interest in this context is the rare earth elements (REEs), because they are analogues of actinides contained within radioactive waste and are tracers of hydrological pathways and geochemical processes. Concentrations of REEs are commonly low in these groundwaters, leading to values below detection limits of standard monitoring methods, particularly for the heavy REEs. We present a new technical set-up for monitoring REEs (and other trace metals) in groundwater in fractured crystalline rock. The technique consists of passing the fracture groundwater, commonly under high pressure and containing reduced chemical species, through a device that maintains the physicochemical character of the groundwater. Within the device, diffusive gradient in thin-film (DGT) discs are installed in triplicate. With this set-up, we studied REEs in groundwater in fractures at depths of approximately -144, -280, and -450 m in granitoids in the A"spo Hard Rock Laboratory in southern Sweden. The entire REE suite was detected (concentrations down to 0.1 ng L-1) and was differently fractionated among the groundwaters. The shallowest groundwater, composed of dilute modern Baltic Sea water, was enriched in the heavy REEs, whereas the deeper groundwaters, dominated by old saline water, were depleted in the heavy REEs. Deployment periods varying from 1 to 4 weeks delivered similar REE concentrations, indicating stability and reproducibility of the experimental set-up. The study finds that 1 week of deployment may be enough. However, if the overall setting and construction allow for longer deployment times, 2-3 weeks will be optimal in terms of reaching reliable REE concentrations well above the detection limit while maintaining the performance of the DGT samplers.
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| 10. |
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| 11. |
- Antonsson, Helena, et al.
(författare)
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Caregivers' reflections on their interactions with adult people with learning disabilities
- 2008
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Ingår i: Journal of Microscopy. - : Wiley. - 0022-2720 .- 1365-2818. ; 15:6, s. 484-91
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Tidskriftsartikel (refereegranskat)abstract
- People with learning disabilities and their professional carers often have difficulty interacting. The aim of this study was to illuminate carers' reflections on their interactions with adult people with learning disabilities. In a previous study, interactions between 16 carers and 11 residents with learning disabilities were recorded on video. In this study, stimulated recall interviews about the interactions were carried out with all the carers. The text was analysed using qualitative content analysis. The findings indicate that the carers reflected on both successful and unsuccessful interaction. Examples of successful interaction included understanding cues, satisfying needs, and managing challenging behaviours, and the carers reflected on the influences that successful interaction had on security, confidence, and satisfaction among the residents. Examples of unsuccessful interaction included failing to understand cues, failing to satisfy needs and failing to manage challenging behaviours, and the carers reflected on the consequences of such interaction, which included irritation, aggression and violence among the residents. Our findings have implications for interventions aimed at strengthening the competence of carers and developing strategies for managing challenging behaviour, in order to ensure high-quality care and a good working climate. © 2008 The Authors.
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| 12. |
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| 13. |
- Antonsson, Helena, et al.
(författare)
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Evaluation of a Web-Based Training Program for Professional Carers Working With People With Learning Disabilities and Challenging Behavior : A Pilot Study with SSED-Design
- 2016
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Ingår i: Issues in Mental Health Nursing. - : Informa UK Limited. - 0161-2840 .- 1096-4673. ; 37:10, s. 734-743
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Tidskriftsartikel (refereegranskat)abstract
- The interaction between people with intellectual disabilities and professional carers is often influenced by communicative difficulties contributing challenging behaviours. The aims of this study were to evaluate to a web-based training program aimed at improving carers' abilities to interact with people with learning disabilities who exhibit challenging behaviours and to explore carers' experiences of participating in such a program. A single-subject experimental design and mixed methods were used to integrate qualitative and quantitative data. Triangulation of questionnaires, interviews with carers, and assessments of one woman's behaviour was performed. The participants were professional carers aged 20 to 55 years. The web-based training program increased carers' abilities to handle challenging behaviours and decreased challenging behaviours in daily care. The program improved the opportunities to offer training to carers who work in community-based accommodations with limited time to receive training.
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| 14. |
- Antonsson, Helena, et al.
(författare)
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Skilled interaction among professional carers in special accommodations for adult people with learning disabilities.
- 2013
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Ingår i: Journal of Psychiatric and Mental Health Nursing. - : Wiley. - 1351-0126 .- 1365-2850. ; 20:7, s. 576-583
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Tidskriftsartikel (refereegranskat)abstract
- Communicative difficulties affect interactions between people with learning disabilities and their carers. Despite such difficulties, however, some carers seem to interact successfully with people who have limited ability to communicate verbally and exhibit challenging behaviour. This study aims to illuminate skilled interaction among carers working in special accommodations for people with learning disabilities. Interactions between 16 caregivers and 11 residents with learning disabilities were recorded on video. Verbal and non-verbal interaction skills among the carers were identified. Four caring situations with people with learning disabilities were chosen to illuminate skilled interaction. The transcribed text was subjected to qualitative content analysis and core stories were created. The results show that skilled interaction between the carers and the people with learning disabilities is based upon being confirming, sharing daily life experience, giving time and space, and using congruent and distinct language. In this paper we present examples that offer concrete suggestions of how to promote successful interaction and create meaning in the shared day-to-day life in special accommodations for people with learning disabilities.
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| 15. |
- Arwidsson, Zandra, 1975-
(författare)
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Organic complexing agents for remediation of heavy metal contaminated soil
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Soil washing of heavy metal contaminated soil may be enhanced by the addition of synthetic chelators. Since many of these chelators may imply stress to soil organisms and are poorly biodegraded, identification and evaluation of effective biodegradable or recyclable chelators (synthetic and/or naturally produced) is of great interest. The efficiency of biodegradable synthetic chelators was evaluated both in bench- (0.3 kg) and meso- (10 kg) scale. Results demonstrated that the solubilization of copper, lead, and zinc was similar in bench- and meso-scale systems, which indicated that these systems could be used in a technical scale. However, the arsenic extraction in meso-scale system, were non-conclusive. Due to the high cost involved in the purchase of synthetic chelating agents, recycling of the solutions is of great interest, and this was achieved in five consecutive washing cycles. Considering the economy of a full-scale process, recycling of complexing solutions with sulfide addition at each cycle, both at the 100 mM-level, appears feasible. Naturally derived chelators were produced by saprotrophic fungi and through alkaline degradation of humic substances and cellulose. The results demonstrated that these types of complexing agents are not as effective as the synthetic chelators. In the fungal systems, desorption of metals was related to production of organic complexing acids, but mainly to the pH-decrease. Nonetheless, in some systems, formation of soluble complexes was indicated (copper). Enhancement of copper, lead, and zinc release with the use of alkaline leachates from wood and peat appeared possible. Since these agents have a natural origin and are derived from rather cheap raw material, recycling is not an issue.
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| 16. |
- Augustsson, Anna, et al.
(författare)
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High metal reactivity and environmental risks at a site contaminated by glass waste
- 2016
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 154, s. 434-443
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Tidskriftsartikel (refereegranskat)abstract
- This study addresses the reactivity and risks of metals (Ba, Cd, Co, Cr, Cu, Ni, Pb, Zn, As and Sb) at a Swedish site with large glass waste deposits. Old glassworks sites typically have high total metal concentrations, but as the metals are mainly bound within the glass waste and considered relatively inert, environmental investigations at these kinds of sites are limited. In this study, soil and landfill samples were subjected to a sequential chemical extraction procedure. Data from batch leaching tests and groundwater upstream and downstream of the waste deposits were also interpreted. The sequential extraction revealed that metals in <2 mm soil/waste samples were largely associated with geochemically active fractions, indicating that metals are released from pristine glass and subsequently largely retained in the surrounding soil and/or on secondary mineral coatings on fine glass particles. From the approximately 12,000 m(3) of coarse glass waste at the site, almost 4000 kg of Pb is estimated to have been lost through corrosion, which, however, corresponds to only a small portion of the total amount of Pb in the waste. Metal sorption within the waste deposits or in underlying soil layers is supported by fairly low metal concentrations in groundwater. However, elevated concentrations in downstream groundwater and in leachates of batch leaching tests were observed for several metals, indicating on-going leaching. Taken together, the high metal concentrations in geochemically active forms and the high amounts of as yet uncorroded metal-rich glass, indicate considerable risks to human health and the environment.
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| 17. |
- Augustsson, Anna, et al.
(författare)
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The risk of overestimating the risk-metal leaching to groundwater near contaminated glass waste deposits and exposure via drinking water
- 2016
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 566, s. 1420-1431
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Tidskriftsartikel (refereegranskat)abstract
- This study investigates metal contamination patterns and exposure to Sb, As, Ba, Cd and Pb via intake of drinking water in a region in southeastern Sweden where the production of artistic glass has resulted in a large number of contaminated sites. Despite high total concentrations of metals in soil and groundwater at the glassworks sites properties, all drinking water samples from households with private wells, located at a 30-640 m distance from a glassworks site, were below drinking water criteria from the WHO for Sb, As, Ba and Cd. A few drinking water samples showed concentrations of Pb above the WHO guideline, but As was the only element found in concentrations that could result in human exposure near toxicological reference values. An efficient retention of metals in the natural soil close to the source areas, which results in a moderate impact on local drinking water, is implied. Firstly, by the lack of significant difference in metal concentrations when comparing households located upstream and downstream of the main waste deposits, and secondly, by the lack of correlation between the metal concentration in drinking water and distance to the nearest glassworks site. However, elevated Pb and Cd concentrations in drinking water around glassworks sites when compared to regional groundwater indicate that diffuse contamination of the soils found outside the glassworks properties, and not only the glass waste landfills, may have a significant impact on groundwater quality. We further demonstrate that different mobilization patterns apply to different metals. Regarding the need to use reliable data to assess drinking water contamination and human exposure, we finally show that the conservative modelling approaches that are frequently used in routine risk assessments may result in exposure estimates many times higher than those based on measured concentrations in the drinking water that is actually being used for consumption. (C) 2016 Elsevier B.V. All rights reserved.
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| 18. |
- Augustsson, Anna, et al.
(författare)
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Trace metals in recharge and discharge ground waters at two sites at the Baltic coast of Sweden
- 2009
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Ingår i: Applied Geochemistry. - : Elsevier BV. - 0883-2927 .- 1872-9134. ; 24:9, s. 1640-1652
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Tidskriftsartikel (refereegranskat)abstract
- The distribution and controls of trace elements (Cd, Cr, Cu, Ni, Pb, Zn and U) in shallow groundwater in discharge and recharge zones were analysed at two sites on the Baltic coast of Sweden; one granite-dominated and one with a significant addition of calcite. Although the study sites differ in overburden geochemistry and groundwater trace metal concentrations, which were well reflected in the general groundwater composition, the relative hydrochemical differences between recharge and discharge ground waters were similar at both sites, and temporally stable. The concentrations of Cd, Cu, Ni and U were higher in soil tubes in recharge areas, but Cr was higher in discharge zones. Also concentrations of HS, Fe, Mn and NH4 were higher in discharge samples, which in combination with increased 34S values provide strong evidence of a transition from oxidizing to more reducing conditions along the groundwater flow gradient. In terms of trace metals, this might mean either mobilisation due to dissolution of trace-metal carrying Fe(III) and Mn(IV) phases, or immobilisation caused by precipitation of discrete trace-metal sulfides or co-precipitation with Fe sulfides. The results from this study show that the latter is dominant in both the carbonate and granite environments for the metals Cd, Cu and Ni. Chromium concentrations were likely coupled to organic complexation and were higher in discharge groundwater, where DOC was also more abundant. As the concentration of several potentially toxic trace metals were found to differ between recharge and discharge areas, a climate driven change in hydrology might have a substantial impact on the distribution of these metals.
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| 19. |
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| 20. |
- Backlund, Krister, et al.
(författare)
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An analytical procedure for determination of sulphur species and isotopes in boreal acid sulphate soils and sediments
- 2005
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Ingår i: Agricultural and Food Science. - : Agricultural and Food Science. - 1459-6067 .- 1795-1895. ; 14:1, s. 70-82
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Tidskriftsartikel (refereegranskat)abstract
- An analytical scheme suitable for boreal acid sulphate (AS) soils and sediments was developed on the basis of existing methods. The presented procedure can be used to quantify and discriminate among acid volatile sulphide, cold chromium reducible sulphur, hot chromium reducible sulphur, elemental sulphur, sulphate sulphur, organic sulphur, total reducible sulphur and total sulphur. The sulphur fractions are recovered as either Ag2S or BaSO4 precipitates and can further be used for isotope analysis. Overlaps between sulphur species are common during speciation, and must be minimized. Some of these overlaps are caused by poor sampling and storage, inappropriate conditions during the distillation, or natural variations in the sample (e.g. Fe3+ interference and grain size). The procedural impact was determined by conducting tests on both artificial and natural samples containing one or several sulphur species. The method is applied on reduced sediment from an AS soil locality (Överpurmo) and a brackish lake (Larsmo Lake) in western Finland and the results, including S-isotopes, are discussed.;
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| 21. |
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| 22. |
- Berger, Tobias, et al.
(författare)
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Fluoride abundance and controls in fresh groundwater in Quaternary deposits and bedrock fractures in an area with fluorine-rich granitoid rocks
- 2016
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 569, s. 948-960
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Tidskriftsartikel (refereegranskat)abstract
- This study focuses on fluoride (F-) concentrations in groundwater in an area in northern Europe (Laxemar, southeast Sweden) where high F- concentrations have previously been found in surface waters such as streams and quarries. Fluoride concentrations were determined over time in groundwater in the Quaternary deposits ("regolith groundwater"), and with different sampling techniques from just beneath the ground surface to nearly -700 min the bedrock (fracture) groundwater. A number of potential controls of dissolved F- were studied, including geological variables, mineralogy, mineral chemistry and hydrology. In the regolith groundwater the F- concentrations (0.3-4.2 mg/L) were relatively stable over time at each sampling site but varied widely among the sampling sites. In these groundwaters, the F- concentrations were uncorrelated with sample (filter) depth and the water table in meters above sea level (masl), with the thicknesses of the groundwater column and the regolith, and with the distribution of soil types at the sampling sites. Fluoride concentrations were, however, correlated with the anticipated spatial distribution of erosional material (till) derived from a F-rich circular granite intrusion. Abundant release of F-from such material is thus suggested, primarily via dissolution of fluorite and weathering of biotite. In the fresh fracture groundwater, the F- concentrations (1.2-7.4 mg/L) were generally higher than in the regolith groundwater, and were uncorrelated with depth and with location relative to the granite intrusion. Two mechanisms explaining the overall high F- levels in the fracture groundwater were addressed. First, weathering/dissolution of fluorite, bastnasite and apophyllite, which are secondary minerals formed in the fractures during past hydrothermal events, and biotite which is a primary mineral exposed on fracture walls. Second, long water-residence times, favoring water-rock interaction and build-up of high dissolved F- concentrations. The findings are relevant in contexts of extraction of groundwater for drinking-water purposes. (C) 2016 Elsevier B.V. All rights reserved.
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| 23. |
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| 24. |
- Berger, Tobias
(författare)
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Fluoride in surface water and groundwater in southeast Sweden : sources, controls and risk aspects
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this thesis is to determine the sources, controls and risk aspects of fluoride in surface water and groundwater in a region of southeastern Sweden where the fluorine-rich 1.45 Ga circular Götemar granite (5 km in diameter) crops out in the surrounding 1.8 Ga granites and quartz monzodiorites (TIB rocks). The materials of this thesis include both primary data, collected for the purpose of this thesis, and a large set of secondary data, retrieved from the Swedish Nuclear Fuel and Waste Management Co., the Swedish Geological Survey and the Kalmar County Council. A characteristic feature of the area is high fluoride concentrations in all kinds of natural waters, including surface waters (such as streams) and groundwater in both the Quaternary deposits (regolith groundwater) and bedrock fractures (fracture groundwater). A number of potential sources and controls of the high fluoride concentrations were investigated, including a variety of geological, mineralogical, mineral-chemical and hydrological features and processes. For the stream waters and regolith groundwater, high fluoride concentrations were correlated with the location of the Götemar granite. This finding is explained by the discharge of fluoride-rich groundwater from fractures in the bedrock and/or the release of fluoride due to the weathering of fluorine-bearing minerals in the Quaternary deposits; however, the Quaternary deposits had considerably lower fluoride concentrations than the underlying bedrock. The high fluoride concentrations in the fresh fracture groundwater (up to 7.4 mg/L) in the TIB-rocks are proposed to be the result of long residence times and the alteration/dissolution of fluorine-bearing primary and secondary minerals along the fracture walls. In terms of risk aspects, this thesis shows that fluoride can add to the transport and inorganic complexation of aluminium in humic-rich, acidic streams. Additionally, 24 % of the children in households with private wells in Kalmar County were assessed to be at risk of excess fluoride intake based on the WHO drinking water guideline value (1.5 mg/L). However, the risk increased significantly when instead the US EPA reference dose (0.06 mg/kg-day) was used, both when all relevant exposure pathways were taken into account as well as water consumption alone. Hence, it is shown that the risk of an excess intake of fluoride is strongly dependent on the basis for evaluation.
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| 25. |
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| 26. |
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| 27. |
- Berger, Tobias, et al.
(författare)
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Fluorine geochemistry of quaternary deposits in a nemo-boreal catchment with elevated dissolved fluoride in surface waters and groundwater
- 2016
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Ingår i: Journal of Geochemical Exploration. - : Elsevier BV. - 0375-6742 .- 1879-1689. ; 170, s. 148-156
-
Tidskriftsartikel (refereegranskat)abstract
- This study focuses on fluorine (F) concentrations and solid-phase speciation in Quaternary deposits, including till, sorted sediments (gravel, sand, clay/silt) and organic-rich soil types, in an area in southeast Sweden underlain by 1.8 Ga granites and quartz monzodiorites with moderate F concentrations (0.11-0.13 wt%) and an outcrop (5 km in diameter) of 1.45 Ga granite (the Gotemar granite) with high to very high F concentrations (0.38-0.54 wt%). Eighteen <1 to 5 m thick profiles were sampled both upon and in the vicinity of the Gotemar granite. The F concentrations in the Quaternary deposits were considerably lower than in the underlying fresh bedrock, with the overall highest concentrations in glacial clay having values up to 660 ppm. A contributing factor to the low F concentrations in the till, as compared to the fresh rock, is release and leaching of fluoride (F-) during alteration of biotite and amphiboles to secondary minerals. Sequential chemical extractions showed that the F in the Quaternary deposits exists mainly in the residual fraction, and also to a substantial extent in phases extractable with hydroxylamine hydrochloride in the till and in phases extractable with Na pyrophosphate in the organic-rich soil types. These features indicate that after release via alteration of primary minerals, F- has to a significant extent been scavenged by Fe/Al (and perhaps Mn) oxyhydroxides in the till and by labile organic matter in the organic soil types. The high F- concentrations previously reported for stream waters and regolith groundwaters in the area are due to weathering and leaching of the Quaternary deposits and discharge of fluoride-rich waters from underlying bedrock fractures. (C) 2016 Elsevier B.V. All rights reserved.
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| 28. |
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| 29. |
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| 30. |
- Berger, Tobias, et al.
(författare)
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Impact of a Fluorine-Rich Granite Intrusion on Levels and Distribution of Fluoride in a Small Boreal Catchment
- 2012
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Ingår i: Aquatic geochemistry. - : Springer Science and Business Media LLC. - 1380-6165 .- 1573-1421. ; 18:2, s. 77-94
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Tidskriftsartikel (refereegranskat)abstract
- This paper explores the influence of a fluorine-rich granite on fluoride concentration in a small boreal catchment in northern Europe. The materials include stream water and shallow groundwater sampled in spatial and temporal dimensions, and analytical data on fluoride and a number of ancillary variables. Fluoride increased strongly towards the lower reaches of the catchment—at the stream outlet the concentrations were up to 4.2 mg L −1 and 1.6–4.7 times higher than upstream. Additionally, fluoride concentrations were particularly high in groundwater and small surface-water bodies (including quarries) above or in direct contact with the granite and showed a strong inverse correlation with water discharge in the stream. Taken together, these data and patterns pin-point the granite intrusion as the ultimate source, explaining the abundance and distribution of dissolved fluoride within the catchment. The granite most likely deliver fluoride to the stream by three mechanisms: (1) weathering of the fine fraction of glacial deposits, derived from the granite and associated fluorine-rich greisen alterations, (2) large relative input of baseflow, partially originating in the granite and greisen, into the lower reaches during low flow in particular, and (3) water-conducting fractures or fracture zones running through the fluorine-rich granite and greisen.
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| 31. |
- Berger, Tobias, et al.
(författare)
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The impact of fluoride on Al abundance and speciation in boreal streams
- 2015
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Ingår i: Chemical Geology. - : Elsevier. - 0009-2541 .- 1872-6836. ; 409, s. 118-124
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Tidskriftsartikel (refereegranskat)abstract
- The impact of fluoride on the abundance and speciation of aluminium (Al) was investigated in three boreal streams characterised by overall high concentrations of fluoride and dissolved organic matter. Stream-water sampling was carried out several times a year for at least 4 years, and a chemical equilibrium model (Visual MINTEQ) was applied in order to model the proportion of colloidal and organically/inorganically complexed Al in the waters. The Al concentrations in filtered (0.45 μm) water samples were inversely correlated with pH, and reached values up to approximately 1. mg/L during low pH conditions (pH < 6.0). In a stream with high fluoride concentrations, as compared to a similar stream with only moderately elevated fluoride concentrations, the Al concentrations were consistently elevated. For the stream with high concentrations of fluoride and Al, the model predicted both high concentrations and proportions of Al-fluoride complexation. This prediction indicates that high fluoride levels contribute to raise both the Al abundance and the ratio of inorganic to organic Al complexation in stream water. In contrast, for another stream with high fluoride concentrations and consistently high (near neutral) pH, there was no evidence of fluoride affecting Al concentration or complexation. These results show that it is important to focus future studies on the role of high levels of dissolved fluoride on both the speciation and the toxicity of Al in stream water.
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| 32. |
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| 33. |
- Björklund, Lars, 1956, et al.
(författare)
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Examinatorns erfarenhet avgör bedömningen
- 2016
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Ingår i: Vetenskapsrådets resultatdialog 2016. - 9789173073363 ; , s. 36-44
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 34. |
- Boman, Anton, et al.
(författare)
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Impact of isostatic land uplift and artificial drainage on oxidation of brackish-water sediments rich in metastable iron sulfide
- 2010
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Ingår i: Geochimica et Cosmochimica Acta. - : Elsevier BV. - 0016-7037 .- 1872-9533. ; 74:4, s. 1268-1281
-
Tidskriftsartikel (refereegranskat)abstract
- This study examines the dynamics of sulfur and trace elements (As, Co, Mo, Ni, Ti and Zn) when brackish-water sediments, unusually rich in metastable iron sulfide (probably a mixture of mackinawite and greigite), are brought into the oxidation zone by postglacial isostatic land uplift and farmland drainage. When subaqueous sediments approach the sea level, metastable iron sulfide is oxidized in the upmost layers and pyrite preserved and even accumulated concomitantly trapping Co, Ni and Zn but not As and Mo. When the land uplift has brought the sediments above sea level and natural drainage thus is initiated, the pyrite is oxidized and Co, Ni and Zn are released and transported down the profile. If this setting remained undisturbed, the slightly oxidized sediment (unripe soil) would become covered by peat and thus protected from further oxidation and metal translocation. Often these sediments are, however, artificially drained resulting in extensive oxidation and fast soil-profile development. The soil is an acid sulfate (AS) soil, characterized by low pH (<4), extensive leaching of metals and an abundance of disseminated brownish Fe(III) precipitates. We suggest that the fast soil development is due to initial oxidation of metastable iron sulfide, followed by pyrite oxidation. Drain bottom sediment, which in terms of chemistry and S-isotopes resembled that of the surfacing sea bottom strata, acted during the sampling period as a sink for metals. The abundant preservation of metastable iron sulfide below the groundwater table, even long periods after uplift above the sea level, is a puzzling feature. We suggest that it is the net result of sulfur starvation, an abundance of Fe(II) and strongly reducing conditions. (C) 2009 Elsevier Ltd. All rights reserved.
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| 35. |
- Boman, Anton, et al.
(författare)
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Isotopic variations of Fe and Zn in Finnish acid sulfate soils
- 2010
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Ingår i: Proceedings of the 19th World Congress of Soil Science. - 9780646537832 ; , s. 1-4
-
Konferensbidrag (refereegranskat)abstract
- The use of a Neptune high-resolution MC-ICP-MS (Thermo Fisher Scientific) in this study has enabled high precision measurements of Fe and Zn isotopic ratios in Finnish acid sulfate soils in one near shore area (Vassor) and one inland area (Rintala).
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| 36. |
- Boman, Anton, et al.
(författare)
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Sulfur dynamics in boreal acid sulphate soils rich in metastable iron sulfide – The role of artificial drainage
- 2008
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Ingår i: Chemical Geology. - : Elsevier BV. - 0009-2541 .- 1872-6836. ; 255:1-2, s. 68-77
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Tidskriftsartikel (refereegranskat)abstract
- The sulfur dynamics of boreal brackish-water sediments rich in metastable iron sulfide (average elemental composition of FeS1.1), which upon oxidation have a huge impact on stream-water chemistry, were studied. Two cores, extending from the upper oxidized layer (acid sulfate soil) into the underlying iron sulfide-bearing sediment (potential acid sulfate soil) were collected at a site close to the sea level and at another site about 40 m above the latter in a region of current isostatic land uplift (Finland). The data clearly show, in contrast to what is often argued, that these notorious acidic soils are formed not as a result of the natural uplift but because of extensive ditching of farmlands. Above the depth of artificial drainage, S and Ni are abundantly lost, while beneath that level pyrite is abundant and metastable iron sulfide is increasing with depth, and the Ni concentration is relatively stable. In the narrow zone between the reduced and oxidized layers, the processes are dynamic and result in preservation of elemental S at one of the locations. The sulfur isotopic composition for metastable iron sulfide and pyrite in the investigated acid sulfate soils were found to be distinctly bimodal and roughly corresponding to a similar distribution in stream-water sulfate earlier reported from the same region. This indicates that pyrite is the main source of sulfate and acidity in some affected drains, while in others it is metastable iron sulfide.
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| 37. |
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| 38. |
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| 39. |
- Brun, Christian, et al.
(författare)
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Spatial distribution of major, trace and ultra trace elements in three Norway spruce (Picea abies) stands in boreal forests, Forsmark, Sweden
- 2010
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Ingår i: Geoderma. - : Elsevier BV. - 0016-7061 .- 1872-6259. ; 159:3-4, s. 252-261
-
Tidskriftsartikel (refereegranskat)abstract
- The spatial distribution of 49 major, trace and ultra trace elements within a Norway spruce system was examined in three sites within the Forsmark area in central Sweden. The system included stemwood, roots, fresh green shoots, litterbags, humus, mineral soil, rhizosphere soil and moss. Based on Principal Component Analysis and manual plots the elements were grouped according to their distribution within the different compartments. One large group of elements occurring abundantly in the soil, and in much lower concentrations in the biota and litter was distinguished, containing mainly elements typically associated with soil minerals. A similar pattern was found for a second group of elements, but with higher concentrations in the biological samples and/or litter. In contrast, there was also one group of elements with high concentrations in biological samples and/or litter and low content in soil. This was mainly nutrients, but also the highly toxic Cd, Hg and Sb. This study is part of the site investigation programme, carried out by the Swedish Nuclear Fuel and Waste Management Company (SKB), in order to locate a suitable area for a deep repository for nuclear fuel waste.
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| 40. |
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| 41. |
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| 42. |
- Carlsson, Mats, et al.
(författare)
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Constraint-based resource allocation and scheduling in steel manufacturing
- 1999. - 1
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Konferensbidrag (refereegranskat)abstract
- This paper describes a flow maximization problem in steel manufacturing, decomposes it into three sub-problems, and models them in terms of finite domain constraints. Greedy algorithms are used for solving the sub-problems. The constraints are used for maintaining consistency rules, not for optimization. A tool implementing these algorithms and equipped with a GUI has been implemented.
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| 43. |
- Carney Almroth, Bethanie, 1974, et al.
(författare)
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Quantifying shedding of synthetic fibers from textiles; a source of microplastics released into the environment
- 2018
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Ingår i: Environmental Science and Pollution Research. - : Springer Science and Business Media LLC. - 0944-1344 .- 1614-7499. ; 25:2, s. 1191-1199
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Tidskriftsartikel (refereegranskat)abstract
- Microplastics in the environment are a subject of intense research as they pose a potential threat to marine organisms. Plastic fibers from textiles have been indicated as a major source of this type of contaminant, entering the oceans via wastewater and diverse non-point sources. Their presence is also documented in terrestrial samples. In this study, the amount of microfibers shedding from synthetic textiles was measured for three materials (acrylic, nylon, polyester), knit using different gauges and techniques. All textiles were found to shed, but polyester fleece fabrics shed the greatest amounts, averaging 7360 fibers/m(-2)/L-1 in one wash, compared with polyester fabrics which shed 87 fibers/m(-2)/L-1. We found that loose textile constructions shed more, as did worn fabrics, and high twist yarns are to be preferred for shed reduction. Since fiber from clothing is a potentially important source of microplastics, we suggest that smarter textile construction, prewashing and vacuum exhaustion at production sites, and use of more efficient filters in household washing machines could help mitigate this problem.
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| 44. |
- Christel, Stephan, et al.
(författare)
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Comparison of Boreal Acid Sulfate Soil Microbial Communities in Oxidative and Reductive Environments
- 2019
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Ingår i: Research in Microbiology. - : Elsevier. - 0923-2508 .- 1769-7123. ; 170:6-7, s. 288-295
-
Tidskriftsartikel (refereegranskat)abstract
- Due to land uplift after the last ice age, previously stable Baltic Sea sulfidic sediments are becoming dry land. When these sediments are drained, the sulfide minerals are exposed to air and can release large amounts of metals and acid into the environment. This can cause severe ecological damage such as fish kills in rivers feeding the northern Baltic Sea. In this study, five sites were investigated for the occurrence of acid sulfate soils and their geochemistry and microbiology was identified. The pH and soil chemistry identified three of the areas as having classical acid sulfate soil characteristics and culture independent identification of 16S rRNA genes identified populations related to acidophilic bacteria capable of catalyzing sulfidic mineral dissolution, including species likely adapted to low temperature. These results were compared to an acid sulfate soil area that had been flooded for ten years and showed that the previously oxidized sulfidic materials had an increased pH compared to the unremediated oxidizied layers. In addition, the microbiology of the flooded soil had changed such that alkalinity producing ferric and sulfate reducing reactions had likely occurred. This suggested that flooding of acid sulfate soils mitigates their environmental impact.
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| 45. |
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| 46. |
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| 47. |
- Coelho, Vera, et al.
(författare)
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Preschool practices in Sweden, Portugal, and the United States
- 2021
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Ingår i: Early Childhood Research Quarterly. - : Elsevier BV. - 0885-2006 .- 1873-7706. ; 55, s. 79-96
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Tidskriftsartikel (refereegranskat)abstract
- Across countries, there are important differences related to the goals, organization, and educational philosophies of care provided to young children prior to formal schooling. Those differences are likely reflected in the classroom practices and teacher-child interactions within a country's early childhood education and care (ECEC) classrooms. This study aims to evaluate the within-country relevance of two classroom observation measures primarily based on a behavioral count approach focused on teacher and child behaviors; and to examine preschool practices in Sweden, Portugal, and the U.S., as they reflect each country's ECEC goals, organization, and educational philosophies. Participants are 78 preschool settings in Sweden, 42 in Portugal, and 168 in the U.S. Results show that the measures targeted culturally-relevant behaviors and provided inter-rater reliability for the behavior count variables in the three countries. Future collaborations may address additional culturally-specific variables. The behavioral descriptions yielded by combining behavioral counts of the measures are analyzed by researchers from the relevant country for insights to the country's values related to early childhood as well as current debates regarding care for children. Measures that provide comprehensive descriptions of classroom settings and apply minimal external or comparative value judgments on the behaviors observed are of practical utility for collaborative international work.
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| 48. |
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| 49. |
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| 50. |
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