| 1. |
- Egervärn, Maria, et al.
(författare)
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Unexpected common occurrence of transferable extended spectrum cephalosporinase-producing Escherichia coli in Swedish surface waters used for drinking water supply
- 2017
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Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 587-588, s. 466-472
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Tidskriftsartikel (refereegranskat)abstract
- The presence of Enterobacteriaceae producing extended spectrum beta-lactamases (ESBL) or transferable AmpC beta-lactamases (pAmpC) is increasingly being reported in humans, food-producing animals and food world-wide. However, the occurrence and impact of these so-called extended spectrum cephalosporinase (ESC)-producing Enterobacteriaceae in aquatic environments are poorly documented. This study investigated the occurrence, concentrations and characteristics of ESC-producing E. coli (ESC-Ec) in samples of surface water collected at five Swedish water treatment plants that normally have relatively high prevalence and concentration of E. coli in surface water. ESC-Ec was found in 27 of 98 surface water samples analysed. All but two positive samples were collected at two of the water treatment plants studied. The ESC-Ec concentration, 1-3cfu/100mL, represented approximately 4% of the total amount of E. coli in the respective surface water sample. In total, 74% of the isolates were multi-resistant, but no isolate was resistant to carbapenems. Six types of ESBL/pAmpC genes were found in the 27 E. coli isolates obtained from the positive samples, of which four (blaCTX-M-15, blaCMY-2, blaCTX-M-1 and blaCTX-M-14) were found during the whole sampling period, in samples taken at more than one water treatment plant. In addition, the genes were situated on various types of plasmids and most E. coli isolates were not closely related with regard to MLST types. The combinations of ESBL/pAmpC genes, plasmids and E. coli isolates were generally similar to those found previously in healthy and sick individuals in Sweden. In conclusion, the occurrence of ESC-Ec in Swedish surface water shows that resistant bacteria of clinical concern are present in aquatic environments even in a low-prevalence country such as Sweden.
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| 2. |
- Volchko, Yevheniya, 1979, et al.
(författare)
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Assessing costs and benefits of improved soil quality management in remediation projects : A study of an urban site contaminated with PAH and metals
- 2020
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Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 707
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Tidskriftsartikel (refereegranskat)abstract
- Contaminants in the soil may threaten soil functions (SFs) and, in turn, hinder the delivery of ecosystem services (ES). A framework for ecological risk assessments (ERAs) within the APPLICERA - APPLICable site-specific Environmental Risk Assessment research project promotes assessments that consider other soil quality parameters than only contaminant concentrations. The developed framework is: (i) able to differentiate the effects of contamination on SFs from the effects of other soil qualities essential for soil biota; and (ii) provides a robust basis for improved soil quality management in remediation projects. This study evaluates the socio-economic consequences of remediation alternatives stemming from a Tier 1 ERA that focusses on total contaminant concentrations and soil quality standards and a detailed, site-specific Tier 3 Triad approach that is based on the APPLICERA framework. The present study demonstrates how Tier 1 and Tier 3 ERAs differ in terms of the socio-economic consequences of their remediation actions, as well as presents a novel method for the semi-quantitative assessment of on-site ES. Although the presented Tier 3 ERA is more expensive and time-consuming than the more traditional Tier 1 ERA approach, it has the potential to lower the costs of remediation actions, decrease greenhouse gas emissions, reduce other environmental impacts, and minimise socio-economic losses. Furthermore, the remediation actions stemming from the Tier 3 ERA were predicted to exert far less negative ES effects than the actions proposed based on the results of the Tier 1 ERA.
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| 3. |
- Titaley, Ivan, 1990-, et al.
(författare)
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Characterization of polycyclic aromatic compounds in historically contaminated soil by targeted and non-targeted chemical analysis combined with in vitro bioassay
- 2021
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Ingår i: Environmental Pollution. - : Elsevier. - 0269-7491 .- 1873-6424. ; 289
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Tidskriftsartikel (refereegranskat)abstract
- Soil samples from a contaminated site in Sweden were analyzed to identify the presence of 78 polycyclic aromatic compounds (PACs) using gas chromatography coupled with mass spectrometry (GC-MS). The target analysis revealed large contributions not only from polycyclic aromatic hydrocarbons (PAHs), but also from alkylated- and oxygenated-PAHs (alkyl- and oxy-PAHs, respectively), and N-heterocyclics (NPACs). PAC profiles indicated primarily pyrogenic sources, although contribution of petrogenic sources was also observed in one sample as indicated by a high ratio of alkylated naphthalene compared to naphthalene. The aryl hydrocarbon receptor (AhR)-activity of the soil extracts was assessed using the H4IIe-pGudluc 1.1 cells bioassay. When compared with the calculated total AhR-activity of the PACs in the target list, 35–97% of the observed bioassay activity could be explained by 62 PACs with relative potency factors (REPs). The samples were further screened using GC coupled with Orbitrap™ high resolution MS (GC-HRMS) to investigate the presence of other PACs that could potentially contribute to the AhR-activity of the extracts. 114 unique candidate compounds were tentatively identified and divided into four groups based on their AhR-activity and environmental occurrence. Twelve substances satisfied all the criteria, and these compounds are suggested to be included in regular screening in future studies, although their identities were not confirmed by standards in this study. High unexplained bio-TEQ fractions in three of the samples may be explained by tentatively identified compounds (n = 35) with high potential of being toxic. This study demonstrates the benefit of combining targeted and non-targeted chemical analysis with bioassay analysis to assess the diversity and effects of PACs at contaminated sites. The applied prioritization strategy revealed a number of tentatively identified compounds, which likely contributed to the overall bioactivity of the soil extracts.
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| 4. |
- Sandager, L, et al.
(författare)
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Storage lipid synthesis is non-essential in yeast
- 2002
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Ingår i: Journal of Biological Chemistry. - 1083-351X. ; 277:8, s. 6478-6482
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Tidskriftsartikel (refereegranskat)abstract
- Steryl esters and triacylglycerol (TAG) are the main storage lipids in eukaryotic cells. In the yeast Saccharomyces cerevisiae, these storage lipids accumulate during stationary growth phase within organelles known as lipid bodies. We have used single and multiple gene disruptions to study storage lipid synthesis in yeast. Four genes, ARE1, ARE2, DGA1, and LRO1, were found to contribute to TAG synthesis. The most significant contribution is made by DGA1, which encodes a novel acyl-CoA;diacylglycerol acyltransferase. Two of the genes, ARE1 and ARE2, are also involved in steryl ester synthesis. A yeast strain that lacks all four genes is viable and has no apparent growth defects under standard conditions. The strain is devoid of both TAG and steryl esters, and fluorescence microscopy revealed that it also lacks lipid bodies. We conclude that neither storage lipids nor lipid bodies are essential for growth in yeast.
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| 5. |
- Bergman, Åke, et al.
(författare)
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Science and policy on endocrine disrupters must not be mixed : a reply to a "common sense" intervention by toxicology journal editors
- 2013
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Ingår i: Environmental Health. - : BioMed Central (BMC). - 1476-069X. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- The "common sense" intervention by toxicology journal editors regarding proposed European Union endocrine disrupter regulations ignores scientific evidence and well-established principles of chemical risk assessment. In this commentary, endocrine disrupter experts express their concerns about a recently published, and is in our considered opinion inaccurate and factually incorrect, editorial that has appeared in several journals in toxicology. Some of the shortcomings of the editorial are discussed in detail. We call for a better founded scientific debate which may help to overcome a polarisation of views detrimental to reaching a consensus about scientific foundations for endocrine disrupter regulation in the EU.
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| 6. |
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| 7. |
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| 8. |
- Poikolainen Rosén, Anton, et al.
(författare)
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Noticing the environment : A design ethnography of urban farming
- 2022
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Ingår i: Proceedings of the 12th nordic conference on human-computer interaction (NordiCHI’22). - New York, NY, USA : Association for Computing Machinery (ACM). - 9781450396998
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Konferensbidrag (refereegranskat)abstract
- Sustainable HCI attempts to shift focus beyond humans, to care for both ourselves and our environment. In this paper, we build on this growing interest and contribute with a design ethnography of urban farming. We focus on practices of observing and gathering data about the environment which we frame as ‘noticing’. In our analysis, three approaches to noticing the environment were iden- tified, and design suggestions were developed for each approach: Green Thumbs (control-oriented), Dirty Nails (sensibility-oriented) and BeeNoculars (appreciation-oriented). The design suggestions, presented as posters, focus on ways to improve the alignment of the acquisition and display of data with the identified approaches. We discuss two themes: the noticing and balancing of systemic rela- tions and needs, and sensory-rich experiences of the environment. The paper contributes to a broader discussion in HCI of how tech- nologies could create a different understanding of and relationship to the environment.
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| 9. |
- Sakhnini, Laila I, et al.
(författare)
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Improving the Developability of an Antigen Binding Fragment by Aspartate Substitutions
- 2019
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Ingår i: Biochemistry. - : American Chemical Society (ACS). - 0006-2960 .- 1520-4995. ; 58:24, s. 2750-2759
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Tidskriftsartikel (refereegranskat)abstract
- Aggregation can be a major challenge in the development of antibody-based pharmaceuticals as it can compromise the quality of the product during bioprocessing, formulation, and drug administration. To avoid aggregation, developability assessment is often run in parallel with functional optimization in the early screening phases to flag and deselect problematic molecules. As developability assessment can be demanding with regard to time and resources, there is a high focus on the development of molecule design strategies for engineering molecules with a high developability potential. Previously, Dudgeon et al. [(2012) Proc. Natl. Acad. Sci. U. S. A. 109, 10879-10884] demonstrated how Asp substitutions at specific positions in human variable domains and single-chain variable fragments could decrease the aggregation propensity. Here, we have investigated whether these Asp substitutions would improve the developability potential of a murine antigen binding fragment (Fab). A full combinatorial library consisting of 393 Fab variants with single, double, and triple Asp substitutions was first screened in silico with Rosetta; thereafter, 26 variants with the highest predicted thermodynamic stability were selected for production. All variants were subjected to a set of developability studies. Interestingly, most variants had thermodynamic stability on par with or improved relative to that of the wild type. Twenty-five of the variants exhibited improved nonspecificity. Half of the variants exhibited improved aggregation resistance. Strikingly, while we observed remarkable improvement in the developability potential, the Asp substitutions had no substantial effect on the antigenic binding affinity. Altogether, by combining the insertion of negative charges and the in silico screen based on computational models, we were able to improve the developability of the Fab rapidly.
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| 10. |
- Wallmark, Joakim, et al.
(författare)
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Efficiency analysis of item response theory kernel equating for mixed-format tests
- 2023
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Ingår i: Applied psychological measurement. - : Sage Publications. - 0146-6216 .- 1552-3497. ; 47:7-8, s. 496-512
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Tidskriftsartikel (refereegranskat)abstract
- This study aims to evaluate the performance of Item Response Theory (IRT) kernel equating in the context of mixed-format tests by comparing it to IRT observed score equating and kernel equating with log-linear presmoothing. Comparisons were made through both simulations and real data applications, under both equivalent groups (EG) and non-equivalent groups with anchor test (NEAT) sampling designs. To prevent bias towards IRT methods, data were simulated with and without the use of IRT models. The results suggest that the difference between IRT kernel equating and IRT observed score equating is minimal, both in terms of the equated scores and their standard errors. The application of IRT models for presmoothing yielded smaller standard error of equating than the log-linear presmoothing approach. When test data were generated using IRT models, IRT-based methods proved less biased than log-linear kernel equating. However, when data were simulated without IRT models, log-linear kernel equating showed less bias. Overall, IRT kernel equating shows great promise when equating mixed-format tests.
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