| 1. |
- Johansson, Fredrik, 1983-
(författare)
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Microscopic Simulation of Pedestrian Traffic
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There has recently been a renewed interest in planning for pedestrian traffic, primarily in connection to public transport interchange stations, since these are important for public transport to constitute an attractive alternative to car usage. This thesis concerns microscopic simulation of pedestrian traffic, which is a promising tool for analyzing and predicting the traffic situation in a given pedestrian facility; particularly powerful when the traffic is congested. Important applications of microscopic simulation include comparison of possible infrastructure designs such as proposed interchange stations, and evaluations of various traffic management solutions, for example information systems.The purpose of this thesis is to advance the capabilities of pedestrian microsimulation toward a level at which it can be reliably applied for quantitative analysis by practitioners in the field. The work is based on an established microscopic model of pedestrian dynamics, the Social Force Model (sfm), and the advances are made in a number of different areas.To be able to evaluate and compare simulated traffic situations suitable performance measures are needed. A set of local performance measures are proposed that quantifies the local delay rate density and estimates the discomfort perceived by the pedestrians.The sfm is extended to include waiting pedestrians through the introduction of a waiting model, demonstrated to be stable and free from oscillations. The inclusion of waiting pedestrians in the model is critical for accurate modelling of public transport interchange stations, where large groups of waiting pedestrians may hinder passing pedestrians if the design of the station is poor.The relaxation time of the adaptation to the preferred velocity is an important parameter in force based models of pedestrian traffic since it affects several behaviors of the simulated pedestrians, two of which are linear acceleration and turning movements. A comparison of observations of accelerating pedestrians reported in the literature and new observations of turning pedestrians indicates that no value of the relaxation time can give model behavior consistent with both sets of observations. This indicates that modifications of the model is needed to accurately reproduce the observed behavior.An important input to simulations is the preferred speed of the simulated pedestrians. The common assumption that the preferred speed distribution at a location does not vary during the day is tested through observations of pedestrian traffic at Stockholm Central Station. The results demonstrate that the preferred speeds are lower in the afternoon than in the morning, implying that the preferred speed should be treated as a source of uncertainty when applying pedestrian microsimulation.Finally, a sensitivity analysis of a simulation of the lower hall of Stockholm Central Station is performed to find the most important sources of uncertainty in the model predictions, given the available data. The results indicate that the uncertainty related to calibration is the largest of the considered potential error sources.
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| 2. |
- Carlsson, Petra, 1974-
(författare)
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Theology beyond Representation : Foucault, Deleuze and the Phantasms of Theological Thinking
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Theology beyond Representation explores the theological opportunities embedded in Michel Foucault’s and Gilles Deleuze’s critique of Christian thinking and of what they regard as a Christian and oppressive logic of representation. Foucault’s and Deleuze’s thoughts on representation are currently discussed in many fields neighbouring theology (e.g. by feminist Karen Barad, Literary theorist Claire Colebrook), but despite the fact that Foucault and Deleuze address some of the most frequently debated issues in contemporary theology, their thoughts on representation have not yet been fully examined in theology.This study offers such an exploration by searching out what new perspectives, forces and notions are brought to light when the critique of representation and the post-representational perspectives in Foucault and Deleuze are allowed to work within theology. It enacts encounters, for example, with the theological contributions of British Radical Orthodox theologian Graham Ward and North American radical theologian Thomas Altizer.The book finally suggests that contemporary theology should perhaps not leave its metaphysics behind but understand its task differently. From a post-representational perspective, the Christian God and inherited Christian dogma may be considered actual, affecting our world in reality – our account of meaning as well as our bodies, actions and politics – yet they are actual and real because they are repeated as such and used as such. The Christian truths are, in short, regarded as phantasms. In consequence, a “post-representational theology” would note the force of form, dogma, truths, authorities, eternal gestures and church buildings, but it would not believe in their final power. It would believe in representation, in its effects and its force, but it would also believe in the possibility of moving beyond its expressions, while also believing that expression already moves beyond representation.Such a perspective, the book argues, could open up a playful yet serious form of post-Christian resistance: To repeat, parody and play with whatever comes to the fore as eternal, or as the truth of concrete experience – both when reading and when doing theology – in order to make room negatively for those realities, actual but unknown, unthinkable yet possible, that no language could ever capture.
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| 3. |
- Johansson, Fredrik
(författare)
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Microscopic Modeling and Simulation of Pedestrian Traffic
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Walking is an environmentally friendly and important mode of transportation. It constitutes the first and last part of almost any trip, regardless of what the main mode of transport is, and is especially important in connection to public transport trips.When designing public transport stations, and similar facilities with large and varying volumes of pedestrian traffic, it is advantageous to be able to predict the traffic conditions at the facility before it is built; discovering too late that the traffic at the facility is inefficient and perceived as uncomfortable may be very costly. To make these predictions we need accurate quantitative models of pedestrian traffic.The foundation of this thesis is the development of a microsimulation platform for pedestrian traffic, the Pedestrian Traffic Simulation Platform (FTSP). The platform is based on the Social Force Model (SFM) and intended for evaluation of proposed designs of pedestrian facilities. A contribution of this thesis is a thorough documentation of the implementation of the FTSP.An extensive literature review of previous research on the SFM revealed gaps in the methodology used to study the properties of the SFM and to interpret its results. This thesis proposes local performance measures to fill this gap. These measures are based on properties of the SFM, and enable quantitative analyses of the quality of service at pedestrian facilities. The proposed measures are applied to the simulation results of some basic scenarios, which reveal previously unknown properties of the SFM. These properties can be used to test the accuracy of the SFM.Another gap in the literature was how to include waiting behavior in the SFM. This thesis shows that accurate modeling of waiting pedestrians is important for the accuracy of the simulation results, and proposes three different extensions to the SFM to model waiting behavior.
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| 4. |
- Siebmanns, Sandra, 1974-, et al.
(författare)
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The effect of nurse-led Internet-based cognitive behavioural therapy for insomnia on patients with cardiovascular disease : A randomized controlled trial with 6-month follow-up
- 2021
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Ingår i: Nursing Open. - : John Wiley & Sons. - 2054-1058. ; 8:4, s. 1755-1768
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To test the effect of nurse-led Internet-based cognitive behavioural therapy for insomnia (I-CBTI), tailored for patients with cardiovascular disease (CVD), with a 6-month follow-up.Design: A two-arm parallel-group randomized controlled trial (RCT) registered at clinicaltrials.gov (NTC03938805) and reported according to the CONSORT checklist.Methods: Forty-eight patients (mean age 72 years, 65% men) diagnosed with CVD and insomnia were randomized to either 9-week nurse-led I-CBTI with support, or an Internet-based self-study programme without support (control group). Insomnia Severity Index (ISI) and Short Form Health Survey (SF-12) were used as primary and secondary outcomes.Results: ISI showed a significant treatment effect of I-CBTI compared to the control group at 9-week follow-up. The mean ISI score in the I-CBTI group at 9 weeks post-treatment was maintained at the 6-month follow-up. Patients' adherence to I-CBTI was associated with a better effect on both the ISI and SF-12.
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| 5. |
- Adman, Per, et al.
(författare)
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171 forskare: ”Vi vuxna bör också klimatprotestera”
- 2019
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Ingår i: Dagens nyheter (DN debatt). - Stockholm. - 1101-2447.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- DN DEBATT 26/9. Vuxna bör följa uppmaningen från ungdomarna i Fridays for future-rörelsen och protestera eftersom det politiska ledarskapet är otillräckligt. Omfattande och långvariga påtryckningar från hela samhället behövs för att få de politiskt ansvariga att utöva det ledarskap som klimatkrisen kräver, skriver 171 forskare i samhällsvetenskap och humaniora.
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| 6. |
- Johansson, David, 1979-
(författare)
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Bacterial toxins for cancer treatment
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Even though anti‐cancer chemotherapy has been continuously improved during the last decades. problems with adverse effects and drug resistance still constitutes a considerable obstacle and sets a demand for new effective treatment options. Tissue homeostasis in multi‐cellular organisms is maintained through intrinsic cell death, apoptosis, which removes unwanted or damaged cells. Disrupted apoptosis is an important factor in tumorgenesis and drug resistance, therefore induction or restoration of apoptotic pathways is also important for the treatment of cancer. Several naturally occurring bacterial toxins have the ability to induce apoptosis and could thus be candidates to complement or improve the therapeutic effect of other anticancer drugs. The bacterial toxins, adenylate cyclase (AC) toxin from Bordetella pertussis, α‐toxin from Staphylococcus aureus and verotoxin‐1 (VT‐1) from Escherichia coli were investigated for their ability to induce apoptosis in different tumor cell lines. Toxin induction of cell death was investigated by cell viability assays, end‐stage apoptosis induction by DNA‐fregmentation (TUNEL) assay. Toxin receptor expression and signal transduction pathways to apoptosis were investigated by flow cytometry, caspase enzyme activity assays and western blot. Immunohistochemistry was used for identification of toxin receptor expression in tumor tissue samples. AC‐toxin was cytotoxic and induced apoptosis in cultured malignant plural mesothelioma (MPM) and small‐cell lung cancer (SCLC) cells. Low‐toxic concentrations of AC‐toxin enhanced cisplatin cytotoxicity and apoptosis in both cell lines. MPM‐cells with acquired cisplatin resistance were more sensitive to α‐toxin than the less resistant parental MPM cell line. A low‐toxic concentration of α‐toxin re‐sensitized resistant MPM cells to cisplatin cytotoxicity by apoptosis induced through the mitochondrial pathway without detectable activation of common up‐stream apoptosis signalling proteins. VT‐1 was highly cytotoxic and induced apoptosis in globotriosylceramide (Gb3) ‐expressing glioma, breast cancer and non‐small‐cell lung cancer (NSCLC) cells but was not cytotoxic to non‐Gb3‐expressing cells. PPMP, an inhibitor of glucosylceramide synthesis which makes exposed cells unable to synthesize Gb3 rendered Gb3‐expressing cells resistant to VT‐1. MPM cells with acquired‐cisplatin resistance expressed Gb3 in contrast to the absent of expression in the less resistant parental cell line. Gb3, could however be up‐regulated by cisplatin in Gb3‐negative MPM‐cells. Presence of a low‐toxic concentration of VT‐1 potentiated cisplatin‐induced cytotoxicity and apoptosis in the cisplatin‐resistance MPM cell line. VT‐1 was a potent inducer of apoptosis, probably via stress‐induced Mitogen‐activated protein kinase (MAPK)‐signaling involving c‐Jun N‐terminal kinase (JNK) and p38, leading to disruption of the mitochondrial membrane integrety, activation of caspase‐9 and ‐3, and ultimately DNA fragmentation and cell death. Gb3 expression was demonstrated in clinical specimens of glioblastoma and breast cancer making these tumor types interesting for further VT‐1 studies. We conclude that bacterial toxins may be used to induce apoptosis in several types of cancer cells. Low concentrations of verotoxin‐1 and α‐toxin may potentially be used to overcome acquired cisplatin‐resistance in cancer patients.
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| 7. |
- Johansson, Peter, 1962-
(författare)
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Health‐related quality of life, depression, sleep and breathing disorders in the elderly : With focus on those with impaired systolic function/heart failure
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim of this thesis was to describe the prevalence of depressive symptoms, sleep disordered breathing (SDB) and sleep complaints, as well as to investigate the prognostic value of health-related quality of life (Hr-QoL) and depressive symptoms on mortality in an elderly community living population with a focus on those with impaired systolic function/heart failure (HF). Descriptive, prognostic and explorative study designs were used to examine if a single question about global perceived health (GPH) is associated with the domains of Hr-QoL as assessed by the SF-36 (I), as well as to evaluate whether GPH provided prognostic information concerning cardiovascular mortality (II). The aim was also to evaluate if depressive symptoms are associated with mortality (III), and to describe the prevalence of SDB and its relationship to impaired systolic function, different insomnia symptoms, as well as excessive daytime sleepiness (IV).In primary care elderly patients with HF, GPH correlated to the physical and mental aspects of Hr-QoL. Patients who rated poor GPH also scored worse physical and mental Hr-QoL compared to patients with good GPH, but the mental aspect of Hr-QoL was however not significant (p<0.07) (I). Moreover, GPH also had an independent association with cardiovascular mortality during a ten-year follow-up. Compared to patients with good GPH, those who scored poor GPH had a four times increased risk for cardiovascular mortality (II). A total of 24% of the patients with HF suffered from depressive symptoms, not significantly different compared to 19% among those without HF. Depressive symptoms were a poor prognostic sign during the six-year follow-up and HF patients with depressive symptoms had the highest risk for cardiovascular mortality compared to HF patients without depressive symptoms (III). SDB is common among elderly people living in the community, almost one quarter (23%) had moderate or severe SDB. However, people with moderate impaired systolic function had a median apnea hypopnea index that was more than twice as high compared to those with normal systolic function (10.9 vs. 5.0, p<0.001). No obvious associations between SDB and excessive daytime sleepiness or the insomnia symptoms; difficulties maintaining sleep; non-restorative sleep; or early morning awakenings were detected. Difficulties initiating sleep were however more common in those with moderate or severe SDB (IV).GPH can be used as a simple tool in clinical routine practice as an aid in identifying patients in need of additional management. SDB is a common phenomenon among elderly people and associated with impaired systolic function, but with a limited impact on subjective sleep complaints. Depressive symptoms were shown to be a poor prognostic sign and may amplify the patient’s experience of suffering. Screening for depressive symptoms could therefore be an important action in the management of patients with HF.
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| 8. |
- Brauer, John, 1988-
(författare)
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Labour Market Policies : Structure and Content, Space and Time
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Labour market policies has two aims: cushioning the economic hardship caused by unemployment and increasing employment rates. In many welfare states, responsibilities for such policies are divided between different political-administrative levels. This dissertation aims to enhance the understanding of labour market policies and especially the involvement of sub-national governmental actors, by analysing the role of municipalities in the Swedish context. The dissertation also investigates the involvement of social work and social workers within labour market policies. A theoretical framework consisting of four pillars, structure, content, space, and time, is used to analyse labour market policies. The analysis combines a historical review with empirical data. The findings show that the involvement of municipalities, in active labour market policies, has taken place against the background of three processes: the multi-level governance of financial support, the shifting role of active labour market policies, and the dialectic relationship between financial support and active labour market policies. The divided responsibility for financial support generates incentives for municipal measures that qualify social assistance recipients for nationally funded social insurances. The fear of work disincentives has also been a driving force in the development of municipal activation. The reliance on municipalities to design and deliver active labour market policies opens for greater crossmunicipal differences. An ongoing reform of the Public Employment Service, the national agency that provides active labour market policies, that decreases the number of local offices and increases the reliance on private service providers, is likely to change the role of municipalities within active labour market policies. Many scholars criticise the involvement of social workers, within labour market policies, given the use of conditionality through activation. This criticism calls for further empirical investigation, not least in terms of how practicing social workers position their work.
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| 9. |
- Dwibedi, Chinmay Kumar, 1987-
(författare)
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Francisella tularensis: persistence, dissemination and source attribution : a theoretical and computational approach
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The bacterium Francisella tularensis causing tularemia in humans and other mammals displays little genetic diversity among genomes across temporal and spatial scales. F. tularensis infects humans with an extremely low infectious dose and causes natural seasonal tularemia outbreaks. During the Cold War, this bacterium was developed as a biological weapon.In paper I, we aimed at investigating the genetic diversity of F. tularensis over space and time and were especially interested in the influence of spatial dispersal on the genetic diversity. By analyses of single-nucleotide polymorphisms (SNPs) among 205 F. tularensis genomes, we found that tularemia had moved from East to West over the European continent by dispersal patterns characterized by multiple long-range dispersal events. Evolutionary rate estimates based on the year of bacterial isolation from 1947 to 2012 indicated non-measurable rates. In outbreak areas with multiple recent outbreaks, however, there was a measurable rate of 0.4 SNPs/genome/year indicating that in areas with more intense disease activity, there is a detectable evolutionary rate. The findings suggest that long-range geographical dispersal events and mostly very low evolutionary rates are important factors contributing to a very low genetic diversity of F. tularensis populations.In paper II, we focused on a geographically restricted area with a history of frequent tularemia outbreaks to study F. tularensis persistence. By analyzing F. tularensis genomes from 138 individuals infected from 1994 to 2010 in Örebro County in Sweden and performing a long-term laboratory storage experiment, we explored the microbial population concept of a pathogen seed-bank. We found that eight indistinguishable genomes – each of them defined by no SNPs across 1.65 million whole-genome nucleotides – locally persisted over 2-9 years. We found unmeasurable SNP accumulation rates and overlapping bacterial generations among the outbreak genomes and that F. tularensis survived in saline for four years without nutrients. By these findings, and analyses of nucleotide substitution patterns, we suggest that a pathogen seed-bank effect is an important feature of F. tularensis ecology influencing genetic diversity.In paper III, we developed a new concept for source attribution of a F. tularensis sample. We aimed to identify genetic variation that is characteristic to laboratory culturing and we used culture amplification to identify genetic variation present at exceedingly low frequencies in a sample. Based on a biological enrichment scheme followed by high-throughput sequencing, we could track genetic variation back to a source sample. These results suggest that the concept has potential for linking a F. tularensis sample to its laboratory source sample.Taken together, the results presented in this thesis provide new understanding of the dissemination patterns and local persistence of tularemia. This is important for the interpretation of molecular epidemiology investigations of the disease. In a wider context, the results demonstrate how spatial dispersal and a microbial seed-bank effect may contribute to the diversity of a disease-causing agent. Finally, we have described a promising concept for source attribution of F. tularensis samples
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| 10. |
- Eriksson, Jonnie, 1978-
(författare)
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Monstret & människan : Paré, Deleuze och teratologiska traditioner i fransk filosofi, från renässanshumanism till posthumanism
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation studies the problem of the inhuman in relation to human nature in philosophy from antiquity to the present, highlighting the interrelationship between science and philosophy in the development of concepts of monstrosity in France from mid-sixteenth century to late twentieth century thought. By means of constraint, it focuses on Ambroise Paré (1509/10–90) and Gilles Deleuze (1925–95) as representatives of early humanism and posthumanism, respectively. The study is divided into four chronologically ordered parts. In part I, four teratological traditions of philosophical import are discerned in antiquity: the naturalist, the humanist, the metaphysical, and the hermeneutical (each associated with a set of key names: in particular, Empedocles, Lucretius; Socrates, Protagoras; Plato, Aristotle; and Pliny, Augustine). Part II follows these traditions into the Renaissance where they intersect in the ‘books of wonder’, among which Paré’s Des monstres et prodiges (1573) is viewed to have had a lasting influence on the development of the science of teratology. Criticizing the positivistic conventions of interpretation of the book in question, notions of order, causality, diversity, and novelty are analyzed for the purpose of excavating from Paré’s work a natural philosophy which hinges on man’s capacity for knowledge; in such a humanist conception, monsters are not so much naturalized as nature becomes monstrous, while man is taken to reflect and encompass all the properties of natural things, thereby incorporating monstrosity in his singular variability. Part III provides an overview of the development of a scientific teratology from Cartesian mechanicism and rationalism, through theories of preformation, epigenesis, and transformation, to the materialist and vitalist debates of the early nineteenth century, when Étienne and Isidore Geoffroy Saint-Hilaire create the discipline of teratology, and its aftermath in developmental and evolutionary biology. The general theme is the place of anomalies in the normal scheme of nature (and culture), as man becomes progressively taken as the norm for thought, ultimately rendering the inhuman as such unthought. Finally, part IV looks to Deleuze as an attempt in the late 1900s to construct a posthumanist philosophy of nature where monstrosity is the problem which rather generates thought; it thus chronologically traces formulations of a concept of monstrosity in his body of work, from the 1940s to the 1990s. In Différence et répétition (1968), Deleuze is found to furnish three interconnected theses to define monstrosity, regarding problems of determination, synthesis, and differentiation, where the problematic as such (the nature of difference itself) is conceptualized as the ‘idea’ of monstrosity, not any particular physical shape. After analyzing the concept of the ‘body without organs’ as an issue of identity and materiality, tracing it back to its formulation in Logique du sens (1969), these theses of monstrosity are then applied to a study of Deleuze’s later philosophy, emphasizing Mille plateaux (1980), Logique de la sensation (1981), and Cinéma 1–2 (1983–85), as side-stepping the human norm in order to think its anomaly (the inhuman) as the condition for creativity. This is evidenced in his ideas of technology and the arts as experimental practices of becoming inhuman. The monster is thus regarded as a ‘conceptual persona’ in a Deleuzian philosophy of the virtual Figure—challenging all actual forms—of an inhuman time for the experience of difference in itself.
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