Publikationer från Uppsala Universitet
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Hidden decomposers : Revisiting saprotrophy among soil protists and its potential impact on carbon cycling
No full textSoil protists are increasingly recognized as key players in organic matter turnover, yet their role as direct decomposers (i.e., saprotrophs) remains underexplored compared to that of bacteria and fungi. Here, we synthesize ecological, physiological, and genomic evidence to highlight the potential of protists to actively decompose organic matter and influence soil carbon cycling. We distinguish two saprotrophic strategies within protists—lysotrophic (extracellular) and phagotrophic (intracellular)—with the latter being unique to protists among microbial decomposers. By directly ingesting particulate or dissolved organic matter, phagotrophic saprotrophic protists may bypass constraints associated with extracellular decomposition, potentially providing an advantage in breaking down recalcitrant substrates. In contrast, lysotrophic saprotrophy in protists involves the secretion of enzymes, similar to bacterial and fungal decomposers. We propose that integrating protist saprotrophy into conceptual and quantitative models of soil organic matter decomposition could address critical knowledge gaps. This integration involves employing functional genomics and functional ecology methodologies to determine, in vitro, the capacity of protists to function as saprotrophs, elucidate the genetic pathways underpinning saprotrophic activities, and assess, in situ, their direct contributions to organic matter decomposition processes. Ultimately, a clearer view of the organic matter decomposition capacities of soil protists will refine our understanding of microbially driven carbon fluxes
Can Survival Scoring Systems for Spinal Metastases be Used to Predict Postoperative Neurologic Recovery? : A Retrospective Study on 204 Patients With Thoracolumbar Metastases Treated at a Tertiary Center
No full textStudy Design: Retrospective Cohort Study. Objective: Scoring systems for metastatic disease of the spine are used to select patients for surgical treatment based on survival estimation, but it is unknown whether they can be used to predict the outcome of surgery. This study aims to investigate the association between two widely used prognostic scores and the neurologic function after surgery. Methods: Retrospective analysis of 204 patients with thoracolumbar metastases treated with decompressive surgery at Karolinska University Hospital (2001-2020). Modified Bauer and Tokuhashi scores were categorized based on surgical indication, and post-operative neurological function was assessed using the Frankel scale at two different post-surgery intervals. Results: Modified Bauer scores ≥2 yielded higher late follow-up Frankel scores (3.9 ± 1.1) than scores <2 (3.5 ± 1.1), P = .03. Modified Tokuhashi scores ≥9 correlated with higher Frankel scores (4.5 ± .9) than scores <9 (3.5 ± 1.1), P < .0001. Both scoring systems positively predicted neurological outcomes at late follow-up, with odds ratios of 1.6 (P = .03) for Bauer and 9.2 (P < .0001) for Tokuhashi. However, only Tokuhashi predicted ambulatory function at late follow-up (P < .0001), demonstrating its utility in prognosticating post-surgical mobility. Conclusion: Higher modified Bauer and Tokuhashi scores were associated with better neurologic function at last follow-up, as well as greater likelihood of being able to walk again. The Tokuhashi score was found to be more accurate than the modified Bauer score in predicting the neurological outcome after surgery
Strategic foresight, knowledge management, and open innovation : Drivers of new product development success
No full textTo remain competitive and make effective decisions in increasingly challenging markets, firms must integrate internal and external knowledge by embedding knowledge management strategies and technologies into their operations. This study aims to examine the roles of strategic foresight and knowledge management in promoting open innovation and driving new product development. Grounded in the knowledge-based view (KBV) of the firm, it investigates how strategic foresight influences open innovation processes and how knowledge management catalyzes innovation success. Using structural equation modelling (SEM) on data collected from 298 technology-based firms located in Lithuania (n = 142) and Slovakia (n = 156), the study demonstrates that strategic foresight directly impacts open innovation and significantly improves new product development through open innovation; in addition, knowledge exploration and exploitation are shown to play important roles in open innovation, with balanced effects on new product development outcomes. The study identifies open innovation as a critical mechanism that links strategic foresight and knowledge management to improve new product development, extending the KBV of the firm by highlighting the integration of external knowledge with internal processes, particularly in smaller, emerging economies. Practically, managers are recommended to prioritize foresight and balanced knowledge management practices while leveraging strategic alliances and networks to improve new product development outcomes. This integrated approach highlights the importance of collaborative innovation and external knowledge in achieving competitive advantage in dynamic business environments
Vascular Stress Markers Following Inhalation of Heated Tobacco Products : A Study on Extracellular Vesicles
No full textThe advent of heated tobacco products (HTPs) has introduced new variables in the study of nicotine delivery systems and their health implications. Amidst concerns over cardiovascular effects, this study aims to elucidate the acute impact of HTP inhalation on extracellular vesicles (EV) levels in young, healthy individuals. In this controlled, acute exposure study, 23 young, healthy volunteers were subjected to HTP inhalation. EV levels of endothelial and platelet origin were quantified through flow cytometry before and after exposure. Data analysis was performed using multiple measures ANOVA to assess changes in EV concentrations. Our findings reveal a significant increase in EVs of endothelial and platelet origin following short-term HTP inhalation with nicotine. Notably, no significant change was observed in leukocyte- and neutrophil-derived EVs. This increase in EVs suggests acute vascular stress, with peak levels observed 4 h post-exposure. The rise in endothelial and platelet-derived EVs aligns with documented responses to acute vascular injury, paralleling the effects seen with traditional cigarette and e-cigarette use. Despite HTPs being marketed as safer alternatives, our results indicate that nicotine-containing HTPs may still pose significant vascular risks. These findings contribute to the growing body of evidence cautioning against the perceived safety of HTPs and reinforce the importance of regulatory oversight and public health initiatives targeting nicotine delivery technologies. Trial Registrations: ClinicalTrials.gov ID: NCT04824495, registered 2021-01-07
Treatment and survival of non-metastatic rectal cancer in patients with inflammatory bowel disease : nationwide cohort study
No full textBackground Patients with inflammatory bowel disease have an increased risk of colorectal cancer. There is a scarcity of large studies with a focus on rectal cancer in patients with inflammatory bowel disease. This study aimed to compare survival in resected patients with rectal cancer with and without inflammatory bowel disease. Methods This national population-based study used the Colorectal Cancer Data Base. All Swedish patients ≥18 years of age with a diagnosis of stage I–III rectal cancer between 1997 and 2021, surgically treated with curative intent, were included and followed up until 2022. The outcome of interest was recurrence-free survival. Flexible parametric survival models adjusted for time since surgery, year of diagnosis, sex, age at diagnosis, and Charlson Co-morbidity Index were used to estimate proportional and time-dependent hazard ratios of recurrence-free survival with 95% confidence intervals. Results Overall, 22 082 patients with rectal cancer were included, among whom 323 (1.5%) had inflammatory bowel disease. Neoadjuvant radiotherapy/chemoradiotherapy was given to 55% and 63% of patients with and without inflammatory bowel disease respectively. The median follow-up time was 5.2 years (interquartile range (i.q.r.) 2.3–10) in patients with inflammatory bowel disease and 5.9 years (i.q.r. 2.9–10) in patients without inflammatory bowel disease. Based on the adjusted proportional hazards model, no overall difference in recurrence-free survival was found (HR 1.05, 95% c.i. 0.87 to 1.26). In the time-dependent adjusted model, patients with rectal cancer with inflammatory bowel disease experienced a lower recurrence-free survival during the first year after surgery (1 year HR 1.36, 95% c.i. 1.06 to 1.73), after which there was no difference in comparison with patients without inflammatory bowel disease (5 years HR 0.77, 95% c.i. 0.56 to 1.06). Conclusion Despite lower recurrence-free survival during the first year among those with inflammatory bowel disease, there were no long-term differences between patients with or without inflammatory bowel disease
How fast does the WallGo? : A package for computing wall velocities in first-order phase transitions
No full textWallGo is an open-source software designed to compute the bubble wall velocity in first-order cosmological phase transitions. Additionally, it evaluates the energy budget available for generating gravitational waves. The main part of WallGo, built in Python, determines the wall velocity by solving the scalar-field(s) equation of motion, the Boltzmann equations and energy-momentum conservation for the fluid velocity and temperature. WallGo also includes two auxiliary modules: WallGoMatrix, which computes matrix elements for out-of-equilibrium particles, and WallGoCollision, which performs higher-dimensional integrals for Boltzmann collision terms. Users can implement custom models by defining an effective potential and specifying a list of out-of-equilibrium particles and their interactions. As the first public software to compute the wall velocity including out-of-equilibrium contributions, WallGo improves the precision of the computation compared to common assumptions in earlier computations. It utilises a spectral method for the deviation from equilibrium and collision terms that provides exponential convergence in basis polynomials, and supports multiple out-of-equilibrium particles, allowing for Boltzmann mixing terms. WallGo is tailored for non-runaway wall scenarios where leading-order coupling effects dominate friction. While this work introduces the software and the underlying theory, a more detailed documentation can be found in https://wallgo.readthedocs.io
The Pursuit of Carried Interest – An Analysis of Legal Certainty in Tax Legislation : With Principles as Guidance in the Grey Zone of Tax Law
No full textParticipation exemption : A critical analysis of when foreign legal entities are equal to Swedish limited companies
No full textA Bayesian Approach to One-Way ANOVA under Heteroscedasticity
No full textThe traditional analysis of variance F test is based on the assumption of homogeneous error variances across all groups, which often fails in real experimental situations. In the frequentist case, Box's approximation (Box, 1954) adjusts the quantile of the F-distribution by adding a scaling factor. Considering the problem from a Bayesian perspective, we study the posterior distribution of the scaling factor under different priors for a one-way ANOVA under heteroscedasticity. The effects of different sample sizes and variance ratios are studied. A comparison with the frequentist method is also carried out. The Bayesian maximum a posteriori (MAP) estimator is used as a counterpart to the frequentist maximum likelihood estimator (MLE). The results show that frequentist estimates outperform the Bayesian method in small or unbalanced samples. As the sample size increases, both approaches yield similar estimates. The role of prior selection in Bayesian models is also highlighted, with Jeffreys' prior yielding the most desirable posterior distributions
The symbolic placement of urban churches : A topographical analysis of early stone churches in the towns of Sigtuna, Lund and Visby
No full textSyftet med denna uppsats är att analysera kyrkotopografiska mönster i tre tidigmedeltida städer tillhörande dagens Sverige. Dessa är Sigtuna, Lund och Visby. Fokus ligger på stenkyrkornas placering, gatunätens utformning och skyddshelgonens betydelse för orienteringen. Dessa strukturer tolkas utifrån teologiska och kosmologiska perspektiv, med särskild betoning på idéer om centralitet, helighet och kristna praktiker. Studien avgränsas till städernas stadskyrkor, varav kloster utesluts och träkyrkor beaktas endast i mån av studiet av kontinuiteter. Källmaterialet består av kartor, arkeologiska rapporter, historiska rekonstruktioner och vetenskaplig litteratur. Genom komparativ metod identifieras återkommande kyrkotopografiska mönster som genom rumsliga enheter formar ett sakralt stadsrum.The purpose of this thesis is to analyze church topographic patterns in three early medieval cities in present-day Sweden. These are Sigtuna, Lund and Visby. The focus is on the location of stone churches, the design of the street network and the importance of patron saints for orientation. These structures are interpreted from theological and cosmological perspectives, with particular emphasis on ideas of centrality, holiness and Christian practices. The study is limited to the urban churches, from which monasteries are excluded, and wooden churches are considered only to the extent of the study of continuities. The source material consists of maps, archaeological reports, historical reconstructions and scientific literature. Through a comparative method, recurring church topographic patterns are identified that, through spatial units, shape a sacred urban space