| 1. |
- Allentoft, Morten E., et al.
(författare)
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100 ancient genomes show repeated population turnovers in Neolithic Denmark
- 2024
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Ingår i: Nature. - 0028-0836 .- 1476-4687. ; 625, s. 329-337
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Tidskriftsartikel (refereegranskat)abstract
- Major migration events in Holocene Eurasia have been characterized genetically at broad regional scales1–4. However, insights into the population dynamics in the contact zones are hampered by a lack of ancient genomic data sampled at high spatiotemporal resolution5–7. Here, to address this, we analysed shotgun-sequenced genomes from 100 skeletons spanning 7,300 years of the Mesolithic period, Neolithic period and Early Bronze Age in Denmark and integrated these with proxies for diet (13C and 15N content), mobility (87Sr/86Sr ratio) and vegetation cover (pollen). We observe that Danish Mesolithic individuals of the Maglemose, Kongemose and Ertebølle cultures form a distinct genetic cluster related to other Western European hunter-gatherers. Despite shifts in material culture they displayed genetic homogeneity from around 10,500 to 5,900 calibrated years before present, when Neolithic farmers with Anatolian-derived ancestry arrived. Although the Neolithic transition was delayed by more than a millennium relative to Central Europe, it was very abrupt and resulted in a population turnover with limited genetic contribution from local hunter-gatherers. The succeeding Neolithic population, associated with the Funnel Beaker culture, persisted for only about 1,000 years before immigrants with eastern Steppe-derived ancestry arrived. This second and equally rapid population replacement gave rise to the Single Grave culture with an ancestry profile more similar to present-day Danes. In our multiproxy dataset, these major demographic events are manifested as parallel shifts in genotype, phenotype, diet and land use.
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| 2. |
- Allentoft, Morten E., et al.
(författare)
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Population genomics of post-glacial western Eurasia
- 2024
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Ingår i: Nature. - 0028-0836 .- 1476-4687. ; 625:7994, s. 301-311
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Tidskriftsartikel (refereegranskat)abstract
- Western Eurasia witnessed several large-scale human migrations during the Holocene1–5. Here, to investigate the cross-continental effects of these migrations, we shotgun-sequenced 317 genomes—mainly from the Mesolithic and Neolithic periods—from across northern and western Eurasia. These were imputed alongside published data to obtain diploid genotypes from more than 1,600 ancient humans. Our analyses revealed a ‘great divide’ genomic boundary extending from the Black Sea to the Baltic. Mesolithic hunter-gatherers were highly genetically differentiated east and west of this zone, and the effect of the neolithization was equally disparate. Large-scale ancestry shifts occurred in the west as farming was introduced, including near-total replacement of hunter-gatherers in many areas, whereas no substantial ancestry shifts happened east of the zone during the same period. Similarly, relatedness decreased in the west from the Neolithic transition onwards, whereas, east of the Urals, relatedness remained high until around 4,000 bp, consistent with the persistence of localized groups of hunter-gatherers. The boundary dissolved when Yamnaya-related ancestry spread across western Eurasia around 5,000 bp, resulting in a second major turnover that reached most parts of Europe within a 1,000-year span. The genetic origin and fate of the Yamnaya have remained elusive, but we show that hunter-gatherers from the Middle Don region contributed ancestry to them. Yamnaya groups later admixed with individuals associated with the Globular Amphora culture before expanding into Europe. Similar turnovers occurred in western Siberia, where we report new genomic data from a ‘Neolithic steppe’ cline spanning the Siberian forest steppe to Lake Baikal. These prehistoric migrations had profound and lasting effects on the genetic diversity of Eurasian populations.
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| 3. |
- Abrahamsson, Marcus, et al.
(författare)
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A study of the performance of risk and vulnerability assessments by Swedish Public Agencies
- 2012
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Ingår i: Proceedings of the 4th International Disaster and Risk Conference: Integrative Risk Management in a Changing World - Pathways to a Resilient Society, IDRC Davos 2012. ; , s. 15-18
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Konferensbidrag (refereegranskat)abstract
- Risk and vulnerability assessments (RVA) are vital components of the work conducted by public agencies at different levels, as part of the processes for governing and managing risks in the society. In Sweden, public agencies at all levels are required by legislation to perform risk and vulnerability assessments within their respective area of responsibility. The present paper presents a study of how Swedish municipalities, county administrative boards and national authorities work with RVAs, with a special focus on three aspects of such assessments that are highlighted in the legislation: vital societal functions, critical dependencies, and capability assessment. The main data collection technique was semi-structured interviews and a total of 25 actors were included and interviewed. The goal was to achieve a good representation of the different actors that perform RVAs. Thus 5 national authorities, 5 county administrative boards, and 15 municipalities were chosen in order to obtain a representative functional distribution (in terms of national authorities responsible for different sectors), geographic distribution as well as size distribution. The study shows that there is rather large variety of approaches, perspectives and views adopted by different actors, all with different advantages and drawbacks. It is argued that the findings of the study can be used to improve the RVA-practices of public authorities.
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| 4. |
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| 5. |
- Abrahamsson, Marcus, et al.
(författare)
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Risk- and vulnerability analyses in crisis management of extreme events - A pilot study
- 2004
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Ingår i: Probabilistic Safety Assessment and Management, vol 1- 6. - 9781852338275 ; , s. 644-649
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Konferensbidrag (refereegranskat)abstract
- In this paper some findings from a pilot study regarding the use of risk- and vulnerability analysis in society's management of extreme events is presented. The study consisted of two major parts. The first part was an interview study with the main objective to generate a preliminary overview of methods and procedures used by 9 selected Swedish governmental agencies in their risk- and crisis management work. The second part, tightly connected to the interview study, was based on literature studies and generated a more general overview of existing risk- and crisis management strategies, risk- and vulnerability analysis methods etc., covering a wide range of government agency areas/sectors. The pilot study was the "starting point" for a long term research program in this field.
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| 6. |
- Andersson, Tilde, et al.
(författare)
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Biogeographical variation in antimicrobial resistance in rivers is influenced by agriculture and is spread through bacteriophages
- 2022
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Ingår i: Environmental Microbiology. - : Wiley. - 1462-2912 .- 1462-2920. ; 24:10, s. 4869-4884
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Tidskriftsartikel (refereegranskat)abstract
- Antibiotic resistance is currently an extensive medical challenge worldwide, with global numbers increasing steadily. Recent data have highlighted wastewater treatment plants as a reservoir of resistance genes. The impact of these findings for human health can best be summarized using a One Health concept. However, the molecular mechanisms impacting resistance spread have not been carefully evaluated. Bacterial viruses, that is bacteriophages, have recently been shown to be important mediators of bacterial resistance genes in environmental milieus and are transferrable to human pathogens. Herein, we investigated the biogeographical impact on resistance spread through river-borne bacteriophages using amplicon deep sequencing of the microbiota, absolute quantification of resistance genes using ddPCR, and phage induction capacity within wastewater. Microbial biodiversity of the rivers is significantly affected by river site, surrounding milieu and time of sampling. Furthermore, areas of land associated with agriculture had a significantly higher ability to induce bacteriophages carrying antibiotic resistance genes, indicating their impact on resistance spread. It is imperative that we continue to analyse global antibiotic resistance problem from a One Health perspective to gain novel insights into mechanisms of resistance spread.
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| 7. |
- Andersson, Tilde, et al.
(författare)
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Enrichment of antibiotic resistance genes within bacteriophage populations in saliva samples from individuals undergoing oral antibiotic treatments
- 2022
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Ingår i: Frontiers in Microbiology. - : Frontiers Media SA. - 1664-302X. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Spread of antibiotic resistance is a significant challenge for our modern health care system, and even more so in developing countries with higher prevalence of both infections and resistant bacteria. Faulty usage of antibiotics has been pinpointed as a driving factor in spread of resistant bacteria through selective pressure. However, horizontal gene transfer mediated through bacteriophages may also play an important role in this spread. In a cohort of Tanzanian patients suffering from bacterial infections, we demonstrate significant differences in the oral microbial diversity between infected and non-infected individuals, as well as before and after oral antibiotics treatment. Further, the resistome carried both by bacteria and bacteriophages vary significantly, with blaCTX-M1 resistance genes being mobilized and enriched within phage populations. This may impact how we consider spread of resistance in a biological context, as well in terms of treatment regimes.
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| 8. |
- Azevedo, Flavio, et al.
(författare)
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Social and moral psychology of COVID-19 across 69 countries
- 2023
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Ingår i: Scientific Data. - : NATURE PORTFOLIO. - 2052-4463. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- The COVID-19 pandemic has affected all domains of human life, including the economic and social fabric of societies. One of the central strategies for managing public health throughout the pandemic has been through persuasive messaging and collective behaviour change. To help scholars better understand the social and moral psychology behind public health behaviour, we present a dataset comprising of 51,404 individuals from 69 countries. This dataset was collected for the International Collaboration on Social & Moral Psychology of COVID-19 project (ICSMP COVID-19). This social science survey invited participants around the world to complete a series of moral and psychological measures and public health attitudes about COVID-19 during an early phase of the COVID-19 pandemic (between April and June 2020). The survey included seven broad categories of questions: COVID-19 beliefs and compliance behaviours; identity and social attitudes; ideology; health and well-being; moral beliefs and motivation; personality traits; and demographic variables. We report both raw and cleaned data, along with all survey materials, data visualisations, and psychometric evaluations of key variables.
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| 9. |
- Baraka, Vito, et al.
(författare)
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Unveiling Rare Pathogens and Antibiotic Resistance in Tanzanian Cholera Outbreak Waters
- 2023
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Ingår i: Microorganisms. - 2076-2607. ; 11:10
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Tidskriftsartikel (refereegranskat)abstract
- The emergence of antibiotic resistance is a global health concern. Therefore, understanding the mechanisms of its spread is crucial for implementing evidence-based strategies to tackle resistance in the context of the One Health approach. In developing countries where sanitation systems and access to clean and safe water are still major challenges, contamination may introduce bacteria and bacteriophages harboring antibiotic resistance genes (ARGs) into the environment. This contamination can increase the risk of exposure and community transmission of ARGs and infectious pathogens. However, there is a paucity of information on the mechanisms of bacteriophage-mediated spread of ARGs and patterns through the environment. Here, we deploy Droplet Digital PCR (ddPCR) and metagenomics approaches to analyze the abundance of ARGs and bacterial pathogens disseminated through clean and wastewater systems. We detected a relatively less-studied and rare human zoonotic pathogen, Vibrio metschnikovii, known to spread through fecal-–oral contamination, similarly to V. cholerae. Several antibiotic resistance genes were identified in both bacterial and bacteriophage fractions from water sources. Using metagenomics, we detected several resistance genes related to tetracyclines and beta-lactams in all the samples. Environmental samples from outlet wastewater had a high diversity of ARGs and contained high levels of blaOXA-48. Other identified resistance profiles included tetA, tetM, and blaCTX-M9. Specifically, we demonstrated that blaCTX-M1 is enriched in the bacteriophage fraction from wastewater. In general, however, the bacterial community has a significantly higher abundance of resistance genes compared to the bacteriophage population. In conclusion, the study highlights the need to implement environmental monitoring of clean and wastewater to inform the risk of infectious disease outbreaks and the spread of antibiotic resistance in the context of One Health.
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| 10. |
- Becker, Per, et al.
(författare)
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Final report: A participatory method for need based capacity development projects and programmes
- 2011
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The three-year research project funded by MSB applies design science, in combination with traditional scientific investigation, to develop a method to guide the planning phase of capacity development projects for disaster risk reduction and climate change adaptation. The method facilitates local participation and ownership as it builds on the strengths of the Logical Framework Approach (LFA), while contextualising it to suit capacity development for disaster risk management and climate change adaptation.
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| 11. |
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| 12. |
- Borell, Jonas, et al.
(författare)
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Krishantering och lärande
- 2010
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Ingår i: FRIVA - risk, sårbarhet och förmåga. - 9789163376917 ; , s. 155-163
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 13. |
- Cedergren, Alexander, et al.
(författare)
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Learning from accident investigations – A cross-country comparison
- 2010
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Ingår i: Proceedings 10th International Probabilistic Safety Assessment & Management Conference..
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Konferensbidrag (refereegranskat)abstract
- This paper compares all accident investigation reports covering railway accidents issued by the national investigation boards in Sweden, Norway and Denmark during a two-year period (2008-2009). By using content analysis, units of text describing attributed causes have been selected and categorized as belonging to one of three hierarchical levels; the micro level (technical malfunctioning and human actions), meso level (organizational actions and factors in the physical environment), and macro level (inter-organizational and regulatory factors). In addition, attributed causes on each level have been further categorized as belonging to different ‘types’ of causes. In a similar manner the recommendations described in all studied reports have been divided into different classes. The results show that the majority of attributed causes in all three countries belong to the micro level, and about half of all recommendations aim at human factors aspects. Furthermore, the diversity in different ‘types’ of causes differs between the countries. The analysis has been followed up by interviews with the investigation boards. Based on these interviews, it can be concluded that the structure, mandate and traditions of the investigation boards influences the outcome of the investigations in such way that a broader mandate gives rise to a higher potential for accidents to be examined from multiple perspectives.
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| 14. |
- Cedergren, Alexander, et al.
(författare)
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Learning from failure: Research initiatives towards improving resilience of the Swedish railway system
- 2009
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Ingår i: 2009 Båstad Conference.
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Konferensbidrag (refereegranskat)abstract
- This paper includes a brief description of some closely related ongoing research activities aiming at learning from failures in order to improve the resilience of the Swedish railway system. One of these activities includes the development of a method aiming at assessing the capability for restoring the service of the railway system after strains affecting its technical, and often highly interdependent, elements. In the event of incidents affecting these technical elements, adequate capability of those actors responsible for restoring the system is important. The method is based on a systems approach, and builds on evaluation of a number of incidents that have occurred on a section of the Swedish railway system in workshop sessions, involving persons with substantial knowledge and experience from recovery operations. By varying these incidents by so-called counterfactual scenarios the capability to return to normal operation after different types and magnitudes of strain can be demonstrated. Hence, the method is useful for evaluating the preparedness for future incidents affecting the railway system. Another study where a similar starting point is used, but where a wider spectrum of serious incidents and accidents form the basis for analysis, is a study focusing on the ability to learn from accidents that have stricken the railway system. Incidents and accidents, and in particular the subsequent accident investigation reports that are issued by the accident investigation boards in Sweden, Norway and Denmark, are studied in order to evaluate their potential for enhancing implementation of lessons learned. Although still in its initial stage, the preliminary results from the study indicate that problems for example stemming from the difficulties in knowledge transfer between different hierarchical levels in society influence the process of learning from accidents. The third study presented in this paper aims at describing the decision making process regarding investments in safety measures in railway tunnel projects. The study is based on interviews with persons involved in six Swedish railway tunnel projects comprising a total of 28 tunnels. The actors involved in the decision making process have considerably different points of departure, which at least in some of the studied projects has proven to be a reason for discussions and disagreements regarding the design of different safety measures. The results from this study show that substantial resources are invested in safety measures in all of the studied projects. However, the study also indicate that there is a need for increased coordination between the different authorities and organizational levels involved in the projects, and that the experience transfer between different projects can be improved. The three case studies are illustrated in an analytical framework that can be used as a basis for further studies, and it can be concluded that the different approaches are valuable in order to improve the resilience of the Swedish railway system.
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| 15. |
- Cedergren, Alexander, et al.
(författare)
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Prerequisites for learning from accident investigations - A cross-country comparison of national accident investigation boards
- 2011
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Ingår i: Safety Science. - : Elsevier BV. - 0925-7535. ; 49:8-9, s. 1238-1245
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Tidskriftsartikel (refereegranskat)abstract
- In this paper railway accident investigation reports issued by the national accident investigation boards in three Scandinavian countries during a 2-year period have been systematically studied. Content analysis of attributed causes in these reports reveals a considerable emphasis on physical processes, actor activities and equipment (the microlevel). Much less attention is paid to organisational factors (the mesolevel) and conditions related to regulators, associations and government (the macrolevel). This means that lessons will primarily be learned about aspects at the lower of these levels. Interviews show that the factors emphasised in investigation reports typically reflect the competences and experiences of the investigators, i.e. they are inclined to focus on areas of their own expertise. Since failures at the microlevel in many cases merely are symptoms of trouble at higher levels, it is argued that competence among investigators that supplements entirely technical or operational backgrounds are necessary for enabling deeper understanding of the factors leading to accidents. One possible way for achieving this is the creation of multi-modal investigation boards that provide a number of potential advantages, such as increased access to specialist competences that are shared between different sectors. Although a multi-modal approach to some degree has been adopted in all three countries, interviews reveal that these positive effects do not emerge automatically. It can therefore be concluded that multi-modal investigation boards offer a number of possible advantages, but only when these synergies are fully exploited can they provide a potential for more effective learning from accidents. (C) 2011 Elsevier Ltd. All rights reserved.
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| 16. |
- Coviello, Andrea D, et al.
(författare)
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A genome-wide association meta-analysis of circulating sex hormone-binding globulin reveals multiple Loci implicated in sex steroid hormone regulation.
- 2012
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Ingår i: PLoS genetics. - : Public Library of Science (PLoS). - 1553-7404 .- 1553-7390. ; 8:7
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Tidskriftsartikel (refereegranskat)abstract
- Sex hormone-binding globulin (SHBG) is a glycoprotein responsible for the transport and biologic availability of sex steroid hormones, primarily testosterone and estradiol. SHBG has been associated with chronic diseases including type 2 diabetes (T2D) and with hormone-sensitive cancers such as breast and prostate cancer. We performed a genome-wide association study (GWAS) meta-analysis of 21,791 individuals from 10 epidemiologic studies and validated these findings in 7,046 individuals in an additional six studies. We identified twelve genomic regions (SNPs) associated with circulating SHBG concentrations. Loci near the identified SNPs included SHBG (rs12150660, 17p13.1, p=1.8×10(-106)), PRMT6 (rs17496332, 1p13.3, p=1.4×10(-11)), GCKR (rs780093, 2p23.3, p=2.2×10(-16)), ZBTB10 (rs440837, 8q21.13, p=3.4×10(-09)), JMJD1C (rs7910927, 10q21.3, p=6.1×10(-35)), SLCO1B1 (rs4149056, 12p12.1, p=1.9×10(-08)), NR2F2 (rs8023580, 15q26.2, p=8.3×10(-12)), ZNF652 (rs2411984, 17q21.32, p=3.5×10(-14)), TDGF3 (rs1573036, Xq22.3, p=4.1×10(-14)), LHCGR (rs10454142, 2p16.3, p=1.3×10(-07)), BAIAP2L1 (rs3779195, 7q21.3, p=2.7×10(-08)), and UGT2B15 (rs293428, 4q13.2, p=5.5×10(-06)). These genes encompass multiple biologic pathways, including hepatic function, lipid metabolism, carbohydrate metabolism and T2D, androgen and estrogen receptor function, epigenetic effects, and the biology of sex steroid hormone-responsive cancers including breast and prostate cancer. We found evidence of sex-differentiated genetic influences on SHBG. In a sex-specific GWAS, the loci 4q13.2-UGT2B15 was significant in men only (men p=2.5×10(-08), women p=0.66, heterogeneity p=0.003). Additionally, three loci showed strong sex-differentiated effects: 17p13.1-SHBG and Xq22.3-TDGF3 were stronger in men, whereas 8q21.12-ZBTB10 was stronger in women. Conditional analyses identified additional signals at the SHBG gene that together almost double the proportion of variance explained at the locus. Using an independent study of 1,129 individuals, all SNPs identified in the overall or sex-differentiated or conditional analyses explained ∼15.6% and ∼8.4% of the genetic variation of SHBG concentrations in men and women, respectively. The evidence for sex-differentiated effects and allelic heterogeneity highlight the importance of considering these features when estimating complex trait variance.
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| 17. |
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| 18. |
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| 19. |
- Grahn, Tonje
(författare)
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A Nordic Perspective on Data Availability for Quantification of Losses due to Natural Hazards
- 2016
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Natural hazards cause enormous amounts of damage worldwide every year. Since 1994 more than 1.35 billion people have lost their lives and more than 116 million homes have been damaged. Understanding of disaster risk implies knowledge about vulnerability, capacity, exposure of persons and assets, hazard characteristics and the environment. Quantitative damage assessments are a fundamental part of disaster risk management. There are, however, substantial challenges when quantifying damage which depends on the diversity of hazards and the fact that one hazardous event can negatively impact a society in multiple ways. The overall aim of the thesis is to analyze the relationship between climate-related natural hazards and subsequent damage for the purpose of improving the prerequisite for quantitative risk assessments in the future. The thesis concentrates on two specific types of consequences due to two types of hazards, 1) damage to buildings caused by lake floods, and 2) loss of lives caused by quick clay landslides. Several causal relationships were established between risk factors and the extent of damages. Lake water levels increased the probability of structural building damage. Private damage reducing measures decreased the probability of structural building damage. Extent of damage decreased with distance to waterfront but increased with longer flood duration while prewar houses suffered lower flood damage compared to others. Concerning landslides, the number of fatalities increased when the number of humans in the exposed population increased. The main challenges to further damage estimation are data scarcity, insufficient detail level and the fact that the data are rarely systematically collected for scientific purposes. More efforts are needed to create structured, homogeneous and detailed damage databases with corresponding risk factors in order to further develop quantitative damage assessment of natural hazards in a Nordic perspective.
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| 20. |
- Guldåker, Nicklas, et al.
(författare)
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Riskhantering i en socken
- 2010
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Ingår i: FRIVA - risk, sårbarhet och förmåga. Samverkan inom krishantering. - 9789163376917 ; , s. 79-92
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Vårt syfte med detta kapitel är att beskriva och analysera krisförberedande arbeten i en landsortsby från en lokal risk- och sårbarhetsgrupps perspektiv samt tydliggöra olika drivkrafter, förutsättningar och relationer med myndigheter och andra aktörer. Underlaget för kapitlet utgörs av en intervju med representanter för den lokala gruppen i en socken i Kronobergs län, en enskild intervju med en nyckelperson i gruppen samt en telefonintervju med ytterligare en nyckelperson i gruppen. De två första intervjuerna genomfördes i november 2008. Telefonintervjun, som kan ses som en återkoppling, genomfördes i januari 2010. Intervjuerna har kompletterats med skriftligt material från den lokala gruppen. Metoden för analys av intervjumaterialet är kvalitativ med stöd av teoribildningar från teknik- och samhällsvetenskaper. I vår analys av den lokala risk- och sårbarhetsgruppens arbete använder vi synsätt och begrepp från aktör-nätverksteorin (ANT) och den tyske sociologen Jürgen Habermas teori om livsvärlden och systemvärlden . ANT hjälper här till att belysa processer för nätverksmobilisering och hur människor och materialiteter kan forma stabila och varaktiga nätverk . ANT bidrar även till att öka förståelsen för drivkrafter och barriärer i den lokala risk- och sårbarhetsgruppens arbeten. Teorin om livsvärlden och systemvärlden hjälper till att öka insikten om medborgares och myndigheters världar och deras problem att förstå varandra och verka ihop. Habermas använder i sin teori begreppet livsvärlden som formar våra personliga identiteter, sociala relationer med vänner, familjer och andra. I den världen inryms också det som kallas kultur och upplevelser. I livsvärlden uppfattas verkligheten från den enskilda individens eller deltagarens synpunkt. Det som Habermas kallar för systemvärlden handlar om myndigheternas och ytterst statens byråkrati samt om marknaden. Marknaden använder pengar, och byråkratierna makt som medel för att styra människors beteenden. Livsvärlden och systemvärlden har olika organisationsformer, rationalitet och sätt att handla .
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| 21. |
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| 22. |
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| 23. |
- Ingwald, Anders, 1965-
(författare)
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Technologies for better utilisation of production process resources
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Most companies today are working in a global environment where competition is hard. In order to be able to survive it is essential that the companies utilise their resources as much as possible in order to keep the production cost low. Maintenance plays a crucial role because of its impact on availability, reliability, quality and life cycle cost (LCC). However, being able to use maintenance proactively so as to increase the utilisation of the production process resources requires access to proper tools and methods for deciding on what maintenance to use and to follow up maintenance impact. Consequently, the overall research problem discussed in the thesis is: How to select a maintenance policy and follow up its performance with respect to cost-effectiveness in order to improve company profitability. In order to solve this overall research problem it has been broken down into four research questions R1: How can different approaches intended for maintaining or improving production process performance assist in the identification, analysis, elimination and prevention of recurrence of problems in a production process?, R2: How should maintenance be selected on the basis of cost-effectiveness?, R3: How should the technical and financial performance of maintenance be measured in order to enable cost-effective improvements? and R4: How to access relevant data required for cost-effective decisions in maintenance?. The philosophical basis applied in the work presented in this thesis is systems theory. When looking at maintenance, it is necessary to have a wide perspective and also see the interaction between maintenance and other relevant working areas. The major contributions that have been achieved and reported in the thesis are: 1. A literature review regarding current approach abilities to identify, analyse and prevent the recurrence of problems, 2. The development of a conceptual model for measuring the maintenance impact through a set of key performance indicators indicating where and how much to invest in maintenance., 3. The development of a maintenance support system for measuring the economic/financial impact of maintenance on both operative and strategic levels, 4. The development of a model for selecting and improving maintenance policies based on cost-effectiveness. The model presented is characterised by being flexible, in the meaning that it is possible to make a selection among any types of maintenance policies., 5. The definition and description of a common database containing relevant data for maintenance management and 6. Results from an exploratory study regarding IT maturity within maintenance management in Swedish industry are presented. The main conclusion of the thesis is that the tools and methods described in this thesis can represent important elements in a system to continuously and cost-effectively improve maintenance performance and thereby better utilise the resources in the production process.
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| 24. |
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| 25. |
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