| 11. |
- Sävje, Fredrik, 1986-
(författare)
-
What would have happened? : Four essays investigating causality
- 2015
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation consists of four self-contained essays.Essay 1. A common method to reduce the uncertainty of causal inferences from experiments is to assign treatments in fixed proportions within groups of similar units: blocking. Previous results indicate that one can expect substantial reductions in variance if these groups are formed so to contain exactly as many units as treatment conditions. This approach can be contrasted to threshold blocking which, instead of specifying a fixed size, requires that the groups contain a minimum number of units. In this essay, I investigate the advantages of respective method. In particular, I show that threshold blocking is superior to fixed-sized blocking in the sense that it always finds a weakly better grouping for any objective and sample. However, this does not necessarily hold when the objective function of the blocking problem is unknown, and a fixed-sized design can perform better in that case. I specifically examine the factors that govern how the methods perform in the common situation where the objective is to reduce the estimator's variance, but where groups are constructed based on covariates. This reveals that the relative performance of threshold blocking improves when the covariates become more predictive of the outcome.Essay 2. Inferences from randomized experiments can be improved by blocking: assigning treatment in fixed proportions within groups of similar units. The use of the method, however, is limited by the difficulty in deriving these groups. Current blocking methods are restricted to special cases or run in exponential time; are not sensitive to clustering of data points; and are often heuristic, providing an unsatisfactory solution in many common instances. This essay introduces an algorithm that implements a new, widely applicable class of blocking—threshold blocking—that solves these problems. Given a minimum required group size and a distance metric, we study the blocking problem of minimizing the maximum distance between any two units within the same group. We prove this is a NP-hard problem and derive an approximation algorithm that yields a blocking where the maximum distance is guaranteed to be at most four times the optimal value. This algorithm runs in O(n log n) time with O(n) space complexity. This makes it the first blocking method with an ensured level of performance that works in massive experiments. While many commonly used algorithms form pairs of units, our algorithm constructs the groups flexibly for any chosen minimum size. This facilitates complex experiments with several treatment arms and clustered data. A simulation study demonstrates the efficiency and efficacy of our blocking algorithm; tens of millions of units can be blocked using a desktop computer in a few minutes.Essay 3. Scholars study political incumbency effects to disentangle how office holding affects subsequent election results. Several types of effects have been discussed and investigated in this time-honored literature, but few have been formally defined. The recent popularity of the regression discontinuity design to investigate the topic has, however, converged the focus to one particular effect: the party incumbency effect. That is, the effect on parties from being an incumbent party. In this essay, I introduce a causal model with which most of the previously discussed effect can be defined. In particular, I can give formal definitions of the incumbent legislator effect—the effect on parties of having an incumbent office holder as candidate—and the personal incumbency effect—the effect on candidates of being the incumbent office holder. Using the model, I decompose the party incumbency effect into these newly defined effects, thereby providing a link between the different effects. The model also allows me to revisit previous estimator and derive which effect they estimate. This investigation reveals that the legislator effect has been in focus in much of the past literature. Motivated by the lack of identification strategies for the personal effect, I introduce several strategies which, under suitable assumptions, can identify the effect. Last, to illustrate these strategies, I investigate the personal incumbency effect in recent Brazilian mayoral elections.Essay 4. Recent research has reported positive effects on schooling, particularly for girls, due to in utero protection from iodine deficiency resulting from iodized oil capsule distribution in Tanzania. These results suggest that similar health interventions might have contributed to the reduction of the educational gender gap and, more generally, unveiled a mechanism through which the natural health environment affects social and economic development. In this essay, we revisit the Tanzanian experience by investigating how these effects differ over time and across surveys; across different treatment specifications; and across additional educational outcome measures. Contrary to previous studies, we find that the estimated effects tend to be small and not robust across specifications or samples. Using all available data and a medically motivated iodine depletion function, we find no evidence of a positive long-run effect of iodine deficiency protection on educational attainment.
|
|
| 12. |
- Wijk, Ingrid
(författare)
-
Experiences of living with type 1 diabetes and improving psychological flexibility through an Acceptance and Commitment Therapy (ACT) intervention
- 2023
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Impaired psychological health in type 1 diabetes is prevalent and associated with elevated glycaemic outcomes. International evidence-based guidelines have defined glycaemic treatment targets to prevent acute and long-term complications. In addition, the guidelines encourage screening for the elevated distress that living with type 1 diabetes may imply. There is a need to gain further understanding of what it means to live with type 1 diabetes as an adult with elevated HbA1c and to develop interventions to promote psychological and physiological health.Aim: The overall aim of the thesis was to describe experiences of living with type 1 diabetes as an adult with elevated HbA1c and furthermore to evaluate the impact of an Acceptance and Commitment Therapy programme for people living with type 1 diabetes. The thesis also aimed to examine the Swedish version of Acceptance and Action Diabetes Questionnaire (AADQ), which is a questionnaire for psychological flexibility related to diabetes.Method and result: In Study I we included 81 adults with type 1 diabetes and HbA1c > 60 mmol/mol in a randomised controlled trial. A seven-session programme based on Acceptance and Commitment Therapy was conducted and the impact on HbA1c, self-management and psychosocial factors was evaluated. No effect was demonstrated in the linear mixed model analysis on HbA1c or the secondary outcomes. Nevertheless, a significant statistical improvement in psychological flexibility was noted one and two years after the intervention. A large drop-out rate was observed in the study. In Study II, the psychometric properties of a translated version of the AADQ were examined through Rasch analysis. A total of 120 adults with type 1 diabetes were included. The Swedish version of the ADDQ showed acceptable psychometric properties such as fit to the Rasch model and person separation index. However, we also found indications on a malfunctioning categorisation of the response categories. A collapsed three category rating was examined. In Study III, two categories of experiences were described in the qualitative interviews: constraining and manageable. Through content analysis, an overarching theme was created "a life-long follower". The theme describes the unrelenting existence of type 1 diabetes that impact life in various degrees.Conclusion: No impact on HbA1c or secondary outcomes could be demonstrated through the Acceptance and Commitment Therapy based programme. At the same time, a key component in psychological health, psychological flexibility, was improved. The Swedish version of the AADQ showed acceptable psychometric quality. However, uncertainties regarding the categorisation should be further examined. The experiences of living with type 1 diabetes as an adult and elevated HbA1c is widely diverse. A person-centred care approach is therefore crucial to support the needs of each unique person with type 1 diabetes.
|
|
| 13. |
- Ackesjö, Helena, 1973-
(författare)
-
Barns övergångar till och från förskoleklass : Gränser, identiteter och (dis-)kontinuiteter
- 2014
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim of this study is to gain knowledge of how the transitions to and from preschool class are described and understood by children. Previous research has indicated that transitions between different school forms can be seen as both problematic and threatening. Transitions should be facilitated and "smooth", something that indicates that continuity is important. Of interest for this study is to gain knowledge of children's perspective of continuities: which continuities and discontinuities children express intransitions.Transitions are theoretically considered as social processes that are constructed, shared and reconstructed together with others. In these processes, children mark and construct borders through speech and action. Their border markings (for example, expression of differences and/or similarities between different communities and between different school forms) also become part of a child's identity constructions.The thesis is based upon the research described in three articles. The empirical data underlying these studies was constructed in a longitudinal ethnographic inspired field work where children have been observed in two transitions between three different school forms: preschool, preschool class and compulsory school.Results suggest that from children’s perspectives the transitions between different school forms contain challenges, opportunities, limitations, changes and preservation. However, the transitions also involve expressions concerning security, risk-taking and include visual markings between the different school forms.One of the conclusions that can be drawn from this work is that it isn’t enough to turn to policy level, such as curricula or even teachers’ aims or aspirations to facilitate these transitions. The child’s perspectives need to be taken into account. Through children's narratives, we have gained knowledge about the opportunities transitions can offer, but also how transitions can be considered as threats or be difficult to interpret for children. This study has also increased our understanding of the importance of continuity as well as discontinuity to mark borders between different school forms.
|
|
| 14. |
|
|
| 15. |
- Andersson, Anna, 1974-
(författare)
-
A framework supporting the collaboration between the logistics- and the product development process
- 2007
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In the competitive environment of today’s global markets, the demands of customers are increasing. They expect to get the best product at the lowest price with immediate availability. Logistics, including transportation, inventory maintenance, order processing, purchasing, warehousing, materials handling, packaging, customer service standards, and product scheduling must continuously be developed to meet the challenges of the market. The globalization, with longer distances to customers and suppliers, and the progressing trend of outsourcing are examples of why the importance of logistics has increased over the last few years.A considerable part of the final product cost is frozen during the early product development phases. In the early phases of the product development process, the cost of making design changes is low compared to making changes later in the product development process. The product development decisions made in the early phases of the product development process have considerable impact on future manufacturing and logistics activities as well.The objective of this research project is to develop a framework supporting the collaboration between the logistics- and the product development process. To do this, it has been essential to analyze which parameters influence the efficiency of the logistics process and the interface between the logistics- and the product development process. Also, to investigate how the logistics department can be integrated earlier in the product development process has been of interest. This has been done through both a theoretical review and also through a number of case studies.The result and conclusion of this project is a framework that gives support for what to focus on, how to collaborate, in which phases collaboration is meaningful, and which persons need to be involved in the different product development phases. Working as the framework suggests will, hopefully, give closer collaboration between the logistics- and the product development process than without this supportive framework. The expectation of the collaboration is an earlier integration of the logistics department in the product development process and through this influence and increase the efficiency of the logistics process.
|
|
| 16. |
- Andersson, Dan, 1967-
(författare)
-
Exploring Perceptions of Route Environments in Relation to Walking
- 2024
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Every walk takes place in a route environment, which can play an important role in deterring or facilitating walking. The focus of this thesis is on the perceptions of environmental variables, and how they relate to appraisals of route environments as hindering – stimulating for walking and unsafe – safe for reasons of traffic, in two metropolitan environments. Another focus is to expand the state of knowledge concerning the criterion-related validity of the Active Commuting Route Environment Scale (ACRES).Methods: Commuting pedestrians in Greater Stockholm, Sweden, were recruited via advertisements. From the inner urban area there were 294 participants (77% women), aged 49.5 years, and from the suburban areas there were 233 participants (82% women), aged 50.0 years. 77 individuals walked in both areas. The participants evaluated their commuting route environments using the ACRES. Correlation, multiple regression, and mediation analyses were used to explore the relationships between the variables. Comparisons of environmental ratings between groups and settings were performed with t-tests. Studies 1 and 2 focused on the inner urban area and studies 3 and 4 on the suburban areas. Studies 1 and 3 focused exclusively on the relations between the four motorized traffic variables (vehicle speed, vehicle flow, noise, and exhaust fumes), and their relations to the outcome variables (hinders – stimulates walking and unsafe – safe traffic). Studies 2 and 4 utilised proxies from studies 1 and 3 and combined them with other environmental variables to further the understanding of route environmental variables in relation to walking.Results: In both areas, aesthetics and greenery were positively related to stimulating walking, whereas noise, a proxy for motorized traffic, was negatively related. Aesthetics was also positively related to unsafe – safe traffic in the inner urban area, whereas greenery had the corresponding role in suburbia. Another important finding was that greenery also influenced aesthetics positively in both areas. Thus, greenery had both a direct and an indirect positive effect. On the other hand, noise influenced aesthetics negatively in the inner urban area, whereas vehicle flow had the corresponding role in suburbia. A number of variables conjointly influenced the outcome unsafe – safe traffic negatively in both areas (speeds of motor vehicles, noise, conflicts, congestion: pedestrians, red lights, and course of the route). The route environment profiles differed distinctly between the two areas.Conclusions: Several route environmental variables appear to be particularly influential in relation to pedestrian commuting, e.g., aesthetics, greenery, and noise. An important finding is that both positive and negative interactions, between certain predictor variables, were disclosed. The contrasting route environment profiles in the different settings strengthen the criterion-related validity of the ACRES. The findings expands the state of knowledge concerning the relations between the environment and walking. If implemented, these findings can influence public health positively.
|
|
| 17. |
- Andersson, Gunnel, 1958-
(författare)
-
Urinary incontinence : prevalence, treatment seeking behaviour, experiences, and perceptions among persons with and without urinary leakage
- 2009
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim of this thesis is to describe urinary incontinence (UI) from a population perspective and to describe experiences and perceptions of UI from an individual perspective. This includes assessing the prevalence of urinary incontinence as well as describing treatment seeking and experiences of living with UI. A secondary aim was to describe the perception of UI among cultures other than the Swedish mainstream, exemplified in this case by Syrian women living in Sweden. Both quantitative and qualitative methods were used, including questionnaires and interviews. Studies I and II were quantitative studies based on a population-based study. Together with a postal survey on general health and living conditions “Life & Health”, a questionnaire on urinary incontinence was sent out to 15 360 randomly-selected residents aged 18-79 in Orebro County, Sweden. In Study I, UI was found to affect 19%. The majority of the respondents experienced minor problems, and only 18% of those reporting UI wanted treatment. However, there was also a group who reported severe problems, but despite this 42% of them did not want treatment. Study II investigated why people with UI refrain from seeking care and treatment. It was found that the desire for treatment was regulated by the frequency of UI, being restricted from participating in various activities, the degree of inconvenience, and the type of UI. Studies III and IV were both qualitative interview studies, describing older women’s experiences of living with UI (Study III) and Syrian women’s perceptions of UI (Study IV). There were similarities between the results of these two studies; the women described UI as a normal and expected problem, and they knew that the district nurse could prescribe incontinence protections and that treatments existed. In both studies, the women expressed difficulties in making contact with the health care service, while the women who did not speak Swedish (Study IV) also had difficulties due to different communication problems. In conclusion, it is important that health care resources are optimized to identify and meet the needs of those who experience major problems with UI, and that there is awareness of the communication difficulties that can be present in meeting with people who speak other languages. However it is also important not to medicalize those who experience minor problems and who have the desire to manage on their own.
|
|
| 18. |
- Andersson, Helene
(författare)
-
MRSA and other resistant bacteria : prevalence, patient and staff experiences, wounds and infection control
- 2012
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Antibiotic resistance has become a major and serious global problem in healthcare. Limited treatment options for infections caused by these organisms can lead to increased morbidity and mortality. Sweden has a low prevalence of antibiotic resistance compared to most other countries but this presents an increasing problem for society and healthcare even in Sweden. The overall aim of this thesis was to illuminate potential problems related to antibiotic resistance from different perspectives: assessing the prevalence of resistant bacteria methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) or other resistant bacteria, and associated wound types, patient and health staff experiences when confronted with resistant bacteria infection, and the occurrence of such infections in the nursing home environment. In the first study a total of 2172 patients admitted to hospital or as out-patient visit at a University hospital during one day were examined with the purpose to identify all wounds, wound types and wound characteristics, and to identify bacteria in all wounds, particularly MRSA, VRE and multi-resistant Gramnegative rods. Four hundred and eight (19%) patients had a total of 668 wounds. Of these, 248 wounds, from 216 patients were cultured. Two unknown MRSA-patients were identified. No patient with VRE was found and there was a low prevalence of other multi-resistant bacteria. In the second study fifteen patients with MRSA infected wounds were interviewed. The aim was to ascertain and describe patients’ knowledge, perceptions and experiences of being MRSA-positive. The interviews were analyzed according to qualitative content analysis. From the analysis three categories and one overall theme were identified. Results showed that information about the MRSA diagnosis often caused a shock-like reaction. The patients’ perception of being MRSA-positive was that it was stigmatizing like the plague or leprosy; they felt dirty and a severe threat to their environment. Fears of infecting someone else and being rejected were commonly expressed. Knowledge and empathy from staff involved in their care was crucial to optimise patients’ experiences. Staff’s needs of education to meet patients’ demands for information, and to prevent spread of antibiotic contamination was essential. In the third study eight nurses and seven assistant nurses from different hospital wards and nursing homes were interviewed regarding their experiences of caring for MRSA-positive patients. Qualitative content analysis was carried out when analysing the data and three themes were identified during the process. Stress and too high workload were factors which were described to cause concerns in the caring situation. A major concern was that nurses felt at risk of becoming infected themselves and then transmitting the infection to other patients and to family members. Knowledge and ignorance about MRSA affected the nurses’ caring; ignorance made them afraid and insecure while knowledge and understanding shaped confidence in their role as caregivers. In the fourth study 560 residents in a total of 67 wards, in nine nursing homes were investigated for prevalence of MRSA, VRE and extended-spectrum β-lactamase (ESBL) - producing Enterobacteriaceae and if carriage of resistant bacteria was related to antibiotic treatment, other risk factors and/or staff´s adherence to guidelines for infection control. In all 296 staff members were interviewed and observed. No resident was positive for MRSA or VRE. Fifteen residents were found to be ESBL-positive. Usage of antibiotics was higher in wards where ESBL-positive residents were detected and there was an indication that there was transmission of ESBL between residents. Staff´s adherence to infection control guidelines sometimes revealed shortcomings but no significant difference regarding adherence to the guidelines could be found. In conclusion: Prevalence of MRSA appears low in both hospitalized patients, out-patients and nursing home residents. Adherence to infection control guidelines among healthcare staff, however, needs further improvement. MRSA colonized patients experienced psychological pressure and stigmatization. Knowledge and empathy from staff involved in their care is crucial to optimise patients’ experiences. Staff education to meet patients' demands for information and the prevention of contamination is essential
|
|
| 19. |
- Capezza, Antonio Jose
(författare)
-
Sustainable Biobased Protein Superabsorbents from Agricultural Co-Products
- 2020
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The preparation of sustainable protein superabsorbents from agricultural industry side-streams is reported. Wheat gluten (WG), a co-product from the ethanol/starch industry, was processed into foams with sponge-like behavior and high liquid uptake. The materials were obtained by phase-separation of aqueous WG dispersions followed by ambient drying, or by lyophilization. The use of a natural and non-toxic cross-linker (genipin) resulted in foams with high water swelling properties (~18 g/g in 10 min). The rapid swelling may be of use in bio-based foams in e.g., sanitary pads.As an alternative, potato protein concentrate (PPC, side-stream from the starch industry), was functionalized and prepared as particles. The liquid swelling capacity was compared after acylation with five different agents. It is shown that the PPC can be acylated to replicate the chemistry of synthetic superabsorbent polymers (SAP), showing water swelling capacity >10 g/g. The acylation (using EDTAD) of WG suspensions resulted in protein particles with water and saline uptake of 22 and 5 g/g, respectively. Limited network stability was however observed when acylating WG in low-protein suspensions. This was addressed by mixing the acylated protein with genipin, which provided a stable protein network. The process gave functionalized particles with swelling capacity ~40 g/g and ~80 % retention of swelling in centrifuge retention tests.The extrusion of WG showed that porous WG with water uptake of 500 % can be produced. Further, the scalability of PPC production was pilot-tested by functionalizing potato fruit juice (PFJ), containing the potato protein in its soluble state before the industrial drying used to obtain PPC. This resulted in water swelling capacities >10 g/g, which was comparable to the PPC-functionalized materials. The results pave the way for future optimization of high-throughput production techniques using protein sources in mass production of sustainable protein-based SAPs.
|
|
| 20. |
- Choi, Sun-Kyoung, 1967-
(författare)
-
Kraften att älska, makten att tjäna : religion, emancipation och den kvinnliga skapande kraften i Jeanna Oterdahls sagor 1908–1927
- 2017
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation studies the Swedish author Jeanna Oterdahl (1879–1965), and the fairy tales and stories she wrote in the period 1908–1927. Oterdahl was a well-known Christian public intellectual in her day. Besides being an author, she worked as a teacher and a lecturer, and was importantly involved in a number of organizations for societal development, such as the Association of the Christian Social Life [Förbundet för kristet samhällsliv] and the Settlement Movement [Hemgårdsrörelsen].The purpose of this study is to investigate the religious elements in her fairy tales and stories, and to study how these elements relate to the ideology of the early Swedish women’s emancipation movement. This movement rejected the conservative Christian faith of the Lutheran State Church, and aligned itself with the liberal form of Christianity that, to a greater extent, recognized the equality of men and women before God.Part I deals with the Christian message of love and its relation to emancipatory elements in Otherdahl’s stories. The point of departure for the analysis is Bremer’s interpretation of the Virgin Mary’s response to God’s calling, "Behold, the Lord’s servant" [Se, Herrens tjänarinna] and its emancipatory meaning. The women of Oterdahl’s stories take the role of servants of the Lord – not Lords [Herrens tjänarinna, inte herrarnas]Part II studies the female characters’ quest for their true (female) selves and their true home where alienation between the sexes will cease to exist and a spiritual kinship can take its place. This true home need not necessarily be a physical place; it can be in the form of an idea or a faith in something higher – such as God – where the self can live and reach its full personal potential. Part II analyzes Oterdahl’s understanding of the female characters’ quest against the background of Emilia Fogelklou’s interpretation of the role of Eve in the Genesis creation narrative (presented in her work “Two fairy tales” [Två sagor]), and against the background of one of Oterdahl’s own lectures, “How We Create a Home” [Hur vi skapa ett hem].The study ends with a discussion of how the concepts of freedom and power figure in Oterdahl’s stories. “Freedom” in Oterdahl’s stories is not a pursuit of power, but has to do with the use of one’s special gifts and with service to others. Freedom, in other words, means to take on responsibilities not only in the private home, but also in the community. Fogelklou describes this as a “human cause” [människosak] – something for women and men to strive for together.By examining how the Christian message of love is expressed through the emancipatory efforts of the female protagonists in Oterdahl’s stories, the dissertation highlights a new dimension in her work, and puts in question the common description of her stories as reactionary. Reinterpreted against the background of the Christian concept of calling/vocation and the ideology of the early emancipationist movement, the seemingly reactionary stories can be understood as emphasizing the importance of women in a changing society.
|
|
