Publikationer från Uppsala Universitet
Not a member yet
127603 research outputs found
Sort by
Förutsättningar för framtida implementering av elektriska flygplan på Skellefteå flygplats : En simuleringsstudie och lastprofilering av nya regionala flygnätverk
No full textThe flight-sector is currently seeing electrification trends that will have far-going impacts on the available charging infrastructure at airports, and as result, new regional flight patterns are expected to emerge while the power profiles corresponding to electric aviation will pose complex challenges in terms of guranteed power capacity. As of today, reasearch is carried out to shine light onto how charging infrastructure can be best implemented to support fleets of electric airplanes on Skellefteå airport. Therefore, it is highly relevant to gain fundamental understandings about the underlying dynamics of systems including electric aviation. To do this, the governing factors of those sytems must first be identified, but since electric aviation is still in an early development phase, there are few real-life examples to inspire new reasearch. Simulation models can therefore be useful to gain unforeseen insights but must be constructed with a high level of validity. In this project, a simulation tool was built using MATLAB and two main simulation studies have been carried out. Initially, a new flight-network was made at Skellefteå airport including all the potential flight destinations within the range of the electric airplane Alice from Eviation and the total load profile at the airport was simulated using a basic charging strategy. Subsequently, the four destinations considered to be most relevant were picked to constitute a more realistic case study and multiple charging strategies were applied while analyzing the resulting load profiles of the airplanes. The results of the simulations indicate strongly that the total power demand of systems including electric aviation is particularly dependent on two major factors: the flight-schedule and the charging strategy applied. It has also become evident that there is a non-trivial correlation between these two and that future simulation studies should put big efforts in constructing systems where flights-schedules and charging strategies are compatible so that power peaks can be minimized. Either way, megawatt peaks are expected and the charging infrastructure at Skellefteå airport is adviced to be dimensioned accordingly. YourFligh
Soil eDNA reflects regionally dominant species rather than local composition of tropical tree communities
No full textEnvironmental DNA (eDNA) is increasingly used for biodiversity monitoring, but validation of the spatial scale(s) at which eDNA reflects extant communities is scarce, particularly in tropical forests: the terrestrial biome with the most concentrated diversity on earth. We leveraged spatially explicit tree inventory data from the 16-ha Luquillo Forest Dynamics Plot (LFDP) in Puerto Rico to validate soil eDNA as a spatially explicit indicator of tree diversity/composition. Using a comprehensive local chloroplast trnL-P6 reference library, we analyzed soil samples at multiple scales through eDNA trnL-P6 metabarcoding. We compared eDNA taxonomic diversity/composition, considering several bioinformatic thresholds, with inventory data across a range of spatial scales, as well as random points to compare observed correlations with random expectations. Despite considerable fine-scale heterogeneity in soil plant eDNA composition, we detected 53 tree Operational Taxonomic Units (OTUs) across the LFDP, corresponding to 68% of tree OTUs from the census data. Encouragingly, this equated to 98% of the total basal area (and 98% of the total stems). An initial confusion matrix evaluation suggested a highly localized eDNA signal (within 5 m of the sampled locations). However, comparison with random expectations revealed a lack of support for a fine-scale spatial signal due to misclassification (i.e., eDNA false presence or/and false absence) of relatively common taxa. Our study shows that "universal" PCR primer metabarcoding of tree eDNA in tropical soils may be useful for assessing dominant taxa at landscape scales, but not for spatially explicit characterization of rare species and community composition at local scales
Molecular and translational studies in small intestinal neuroendocrine tumors
No full textSmall intestinal neuroendocrine tumors (SI-NETs) are the most common malignancy of the small intestine. They are typically slow-growing, often presenting with multiple primary tumors and, in many cases, metastases at diagnosis. Radical surgery remains the only curative option, yielding a five-year survival rate of approximately 67%. However, the lack of comprehensive molecular understanding limits the availability of personalized treatment strategies. The aim of this thesis was to further characterize the molecular landscape of SI-NETs using state-of-the-art genomic and transcriptomic tools. In Paper I, long-read whole-genome sequencing revealed few recurrent structural variants across samples. The most notable consistency was found in the frequency of deletions and insertions between tumors. In the chromosome 18 methylation subgroup analysis, we identified a general hypomethylation trend across the genome, but with contrasting hypermethylation patterns in genes located on the chromosome 18. In Paper II, we explored alternative splicing differences between primary tumors and liver metastases using full-length transcript analysis. Only a small number of recurrent differences emerged across analytical approaches, and their functional consequences were difficult to predict. A comparative analysis using corresponding short-read transcriptomes did not reveal consistent splicing alterations, highlighting the lack of or complexity of splicing variation in SI-NETs. Building on our earlier in vitro experiments of metformin’s anti-tumor effects in SI-NET cell lines, Paper III reports an in vivo follow-up in which oral metformin administration to tumor xenografted mice significantly inhibited tumor growth. Analysis of mRNA and miRNA expression patterns identified potential treatment-induced miRNA biomarkers. External single-cell RNA sequencing data further validated a subset of genes particularly relevant to SI-NET biology. In Paper IV, we applied single-cell RNA sequencing to distinguish molecular differences between SI-NET tumor cells and their presumed cell of origin, the rare enterochromaffin (EC) cell. A clear distinction between SI-NET tumor cells and EC cells revealed 373 significantly altered genes; among these, 26 exhibited tumor-specific activation or silencing. While some of these changes corroborated previous findings, several novel gene expression shifts were identified, offering new insight into tumor initiation and progression
UNRWA’s Public Discourse Impact on Palestinian Liberation from Colonialism
No full textThis thesis conducts a critical analysis of the discourse present in the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA)’s official annual reports to determine the extent to which they engage with or circumvent the foundational political project of Palestinian liberation from settler colonialism. Situated at the intersection of critical humanitarian studies, postcolonial theory, and political discourse analysis, the research addresses a significant gap in the literature: while the depoliticizing effects of the international aid architecture on Palestinian civil society are well-documented (Jad, 2007; Alashqar, 2018), a systematic, empirical examination of how this depoliticization is linguistically operationalized by a major UN agency remains underexplored. To investigate this, the study employs Critical Discourse Analysis (CDA), specifically Fairclough’s (1995) three-dimensional model, as its methodological framework. A purposive sample of five annual reports from key historical junctures (1995, 2002, 2009, 2017, 2022) is subjected to a close textual analysis. The investigation focuses on linguistic features such as nominalization and passivation, which are examined for their capacity to obscure agency and power dynamics (Fairclough, 1995). The analysis is further contextualized within broader theoretical frameworks of NGOization and the depoliticization of aid (Ferguson, 1994; Li, 2007), which explain the structural pressures shaping UNRWA’s communicative strategies. The empirical findings reveal a consistent and powerful pattern of depoliticization across all reports. The analysis identifies four interlocking thematic strategies: the systematic erasure of the Israeli state as an agent of violence through grammatical passivation; the displacement of political narratives by a technocratic focus on service delivery metrics; the strategic ambiguity in the application of a "protection" mandate; and the recent ascendancy of a "resilience" paradigm that individualizes suffering. Through these discursive mechanisms, themes of liberation, resistance, and decolonization are consistently avoided or reframed into apolitical, managerial terms. The discussion argues that these linguistic patterns are not neutral but represent a discursive manifestation of the power dynamics inherent in the donor-funded humanitarian system. The thesis concludes that UNRWA’s official discourse actively participates in a structure of power that manages and contains Palestinian political aspirations, thereby contributing to the perpetuation of the colonial status quo rather than challenging it. This research contributes to academic debates on the decolonization of aid (Aloudat & Khan, 2022) by providing concrete evidence of how depoliticization works linguistically, and it urges a critical reevaluation of communicative strategies in humanitarian practice, arguing that in contexts of settler colonialism, the presumption of neutrality functions as a form of complicity.
Computationally efficient upscaling of Markovian occupancy models for urban-level building simulations
No full textDespite recent progress in the field of urban building energy modelling (UBEM), integration of occupant behaviour models is still an area in need of development. Although abundant for building energy modelling (BEM), stochastic occupancy models tailored for urban-level simulations are lacking, as well as systematic analyses of accuracy versus complexity. Occupancy models aimed for BEM typically introduce a heavy computational load, but a small reduction in accuracy might allow a large increase in speed. This paper proposes methods for scaling up stochastic Markov-chain (MC) occupancy models previously developed for BEM to fit UBEM, and compares them in terms of accuracy and computational efficiency. For the scales normally involved in UBEM (tens to hundreds of occupants per zone and hourly time resolution), a model based on multinomial sampling is proposed that is several hundred times faster than the original MC model and only slightly overestimates the variability in the occupancy patterns
Computing Education in Sweden : Unequal Participation in a Changing Field
No full textThis position paper explores unequal participation in computing education within Sweden, offering a comprehensive analysis across multiple educational levels and institutional contexts. Drawing on national data and case studies, the paper examines participation trends in high school study programmes, higher education fields, and at Uppsala University, one of Sweden's leading institutions. The discussion addresses ambiguities in the definitions of "computing," "ICT," and "digital competency" and how this impacts the development of computing education in Sweden and beyond. We identify key factors shaping participation, including gender disparities, family background, and programme-specific barriers, and situate these findings within the broader evolution of the field. While this work is in its early stages, it aims to provide valuable insights for educators, policymakers, and researchers to address inequalities and foster inclusive computing education in a rapidly changing digital landscape
Patient experiences of narcolepsy and idiopathic hypersomnia in the Nordics : a patient journey map
No full textCentral disorders of hypersomnolence (CDH) are chronic diseases that significantly impact the lives of affected individuals. We aimed to explore the perspectives of individuals with narcolepsy type 1 (NT1), narcolepsy type 2 (NT2), and idiopathic hypersomnia (IH), and the challenges they encounter in their daily lives and within the healthcare systems in the Nordics. Interviews with patients (N = 41) and healthcare professionals (n = 14) and a patient survey (n = 70) were conducted in 2022 in Denmark, Sweden, Finland, and Norway to develop a patient journey map that visualises the patient with CDH journey and provides insights into the difficulties faced by these individuals. The patient journey mapping approach was chosen to focus on the processes and experiences of patients, highlighting the challenges they confront. Our findings revealed that the process of receiving a CDH diagnosis, as well as subsequent misdiagnoses and treatment, can be protracted and burdensome. CDH diagnoses remain poorly understood by neurologists, general practitioners, and the public, resulting in adverse consequences, with patients reporting a mean (standard deviation [SD]) time from symptom onset to diagnosis of 8.4 (5.11) years and a mean (SD) of 5.5 (4.17) productive hours lost/day. The available non-pharmaceutical support for patients with CDH, encompassing medical, psychological, educational, and professional assistance, was insufficient. The generalisability of the findings to one specific diagnosis is limited due to the collective analysis of the CDH. These findings are invaluable for identifying disruptions in the patient with CDH journeys and for designing improved pathways for those with NT1, NT2, and IH in the future
Locoregional progression and surgical indications in stage IV asymptomatic SI-NETs
No full textSmall intestinal neuroendocrine tumors are often diagnosed at an advanced stage, with up to 70% of patients presenting with stage IV disease. While some guidelines recommend prophylactic resection of the primary tumor and mesenteric lymph node metastasis in patients without abdominal symptoms at diagnosis to prevent future abdominal complications, the benefit of this approach remains uncertain.This retrospective cohort study included 44 asymptomatic patients with stage IV small intestinal neuroendocrine tumors treated at Uppsala University Hospital between 2014 and 2019. Additional ten symptomatic patients who underwent at least two computed tomography scans before planned surgery were included in the analysis of mesenteric metastasis volume change and tumor growth rate. The primary outcomes were abdominal symptoms development requiring surgical intervention and the assessment of mesenteric metastasis size progression. During a 10-year follow-up, only four initially asymptomatic patients (9%) developed symptoms leading to surgery. Among all 54 patients, the median volume change in mesenteric metastases was -298 mm3 (IQR: -2,785-1,294), with no significant difference between baseline and most recent scans (P = 0.38). The median interval between scans was 29 months, and the median tumor growth rate was -0.6% per month (IQR: -3.6-1.9%). Similar results were observed in the asymptomatic group. These findings suggest that a non-operative management in stage IV patients without abdominal symptoms is associated with a low incidence of symptom development and limited progression of mesenteric metastases