Publikationer från Uppsala Universitet
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Avances hacia la ejecución concurrente y no especulativa de secciones críticas
No full textParallel programs require, besides the cache orchestration, another mechanism that guarantees synchronization among other threads of the same program.These synchronization mechanisms will induce overheads, by slowing down certain operations and stalling threads, among many others, to comply with the requirements established by the programmer. The thesis's objective is the efficient execution of critical sections, that is, regions of code that must be executed atomically.The most efficient method is the concurrent and non-speculative executions of these sections.To achieve this, we present the 3 steps we have taken:1) single-atomic instructions can be used to implement non-speculative critical sections, therefore, we develop an updated version of the well-known Splash benchmark suite that uses single-address atomic instructions to implement most of the critical sections (Splash-4);2) a new set of multi-address atomic instructions, and a methodology on how to efficiently implement them, that can be used for small critical sections (MADs);3) without the direct intervention of the programmer, a more generic method that limits the retries required to execute contended critical regions (CLEAR). For an efficient evaluation of the results, we have used the most up-to-date tools possible in each case, and even, when possible, real machines instead of simulations.For the simulations, we have used the gem5 simulator, at all times performing multiple runs.The simulator has been configured to emulate, as reliably as possible, processors based on the latest intel generations. In our first step, Splash-4, we have managed to reduce the execution time by using 64-cores by 50%, while maintaining the original structure and algorithms.In the second objective (MADs), the new atomic instructions implemented, reduce execution time by 80% compared to the classical lock mechanism, and by 60% by using a transitional memory technique similar to intel TSX, adding only 68 bytes per core.Finally, CLEAR is able to limit the number of re-executions of critical sections executed under speculative methods, increasing by 35% the number of sections that complete on the first retry, and reducing from 37% to 15% the number of sections that need to reach fallback. All this improving the execution time by 35% against an Intel TSX implementation and 23% against PowerTM
Preeclampsia and the brain : The blood-brain barrier and neurological consequences
No full textCerebral complications of preeclampsia are among the leading causes of maternal mortality. Women with previous preeclampsia and eclampsia have increased long-term risks of cognitive impairment, stroke, and vascular dementia. They report a lower quality of life, concentration issues, and tiredness after childbirth. The pathophysiology of cerebral complications remains unclear, however, is suggested to involve blood-brain barrier (BBB) impairment, loss of cerebral autoregulation, microinfarctions, and edema. This translational thesis aimed to explore pathophysiological mechanisms of BBB impairment in preeclampsia and to investigate whether preeclampsia and eclampsia increase the risk of neurological disorders and sick leave in the years following childbirth. This was explored through two preclinical laboratory studies and two register-based cohort studies. The BBB was explored using an in vitro model. Results were correlated to plasma concentrations of cerebral biomarkers. Correlations were estimated with non-parametric tests. Plasma from women with preeclampsia affected the in vitro model of the human BBB by increasing permeability to FITC-Dextran and decreasing transendothelial electrical resistance (TEER) at the cellular level. All cerebral biomarkers were increased in plasma from women with preeclampsia, compared with normotensive pregnancy. Increased plasma concentrations of NfL were correlated to a decrease in TEER over the BBB. Plasma concentrations of tau, NSE and S100B were not associated with TEER. Associations between gestational hypertension, preeclampsia and eclampsia, and a composite of neurological disorders (migraine, headache, epilepsy, sleep disorders and neurasthenia) were estimated with multivariate Cox regression models. All exposure groups were associated with an increased risk of a composite of neurological disorders, compared with normotensive pregnant women. Gestational hypertension and preeclampsia were associated with increased migraine risk. The strongest association was found between eclampsia and epilepsy. Associations between preeclampsia and sick leave rates in the second year postpartum were assessed with augmented inverse probability weighting. Women with preeclampsia took more sick leave compared with women without preeclampsia. In conclusion, plasma from women with preeclampsia impairs BBB function in vitro, and BBB leakage is indicated by correlation between decreased TEER and increased plasma NfL. Women with preeclampsia, particularly eclampsia, face a higher risk of developing neurological disorders postpartum, which may reflect the increased sick leave observed in this group
Balancing Privacy and Innovation : - Exploring the Conflict Between Data Protection Rights and Blockchain's Immutability and Decentralized Nature
No full textHigh incidence of permanent pacemaker after Cox-maze IV and mitral valve surgery : a nationwide registry-based study
No full textOBJECTIVES This study evaluated the long-term risk of permanent pacemaker implantation following Cox-maze IV (CMIV) and concurrent mitral valve surgery. METHODS A retrospective, nationwide, registry-based analysis was conducted on postoperative permanent pacemaker implantation in 397 patients with symptomatic mitral valve insufficiency and atrial fibrillation who underwent CMIV and mitral valve surgery in Sweden between 2009 and 2017. They were compared to a registry group of 346 patients with atrial fibrillation who underwent mitral valve surgery without surgical ablation during 2014–2017. The follow-up ended on 30 September 2022. RESULTS CMIV patients were on average 4 years younger and had lower surgical risk than registry patients. More CMIV patients underwent early (<30 days) pacemaker implantation (13.3% vs. 5.5%, P = 0.002). CMIV patients had a doubled adjusted risk of requiring a pacemaker compared to registry patients after 8 years [HR 1.96, 95% CI 1.27–3.04]. In the CMIV group, 22% (95% CI 18–26%) had a pacemaker by 5 years, increasing to 27% (95% CI 22–31%) by 8 years, compared to 13% (95% CI 10–17%) at both time intervals in the registry group. Atrioventricular block II/III accounted for >60% of early pacemaker indications in both groups, and sinus node dysfunction was the indication for late pacemaker implantation in 48% in the CMIV group. CONCLUSIONS Patients undergoing CMIV concomitant with mitral valve surgery have a higher rate of postoperative pacemaker implantation compared to patients with atrial fibrillation undergoing mitral valve surgery alone. Sinus node dysfunction was the main indication for late pacemaker among CMIV patients
Euclid preparation : LVIII. Detecting extragalactic globular clusters in the Euclid survey
No full textExtragalactic globular clusters (EGCs) are an abundant and powerful tracer of galaxy dynamics and formation, and their own formation and evolution is also a matter of extensive debate. The compact nature of globular clusters means that they are hard to spatially resolve and thus study outside the Local Group. In this work we have examined how well EGCs will be detectable in images from the Euclid telescope, using both simulated pre-launch images and the first early-release observations of the Fornax galaxy cluster. The Euclid Wide Survey will provide high-spatial resolution VIS imaging in the broad I-E band as well as near-infrared photometry (Y-E, J(E), and H-E). We estimate that the 24 719 known galaxies within 100 Mpc in the footprint of the Euclid survey host around 830 000 EGCs of which about 350 000 are within the survey's detection limits. For about half of these EGCs, three infrared colours will be available as well. For any galaxy within 50 Mpc the brighter half of its GC luminosity function will be detectable by the Euclid Wide Survey. The detectability of EGCs is mainly driven by the residual surface brightness of their host galaxy. We find that an automated machine-learning EGC-classification method based on real Euclid data of the Fornax galaxy cluster provides an efficient method to generate high purity and high completeness GC candidate catalogues. We confirm that EGCs are spatially resolved compared to pure point sources in VIS images of Fornax. Our analysis of both simulated and first on-sky data show that Euclid will increase the number of GCs accessible with high-resolution imaging substantially compared to previous surveys, and will permit the study of GCs in the outskirts of their hosts. Euclid is unique in enabling systematic studies of EGCs in a spatially unbiased and homogeneous manner and is primed to improve our understanding of many understudied aspects of GC astrophysics
Clinical experience in open robotic-assisted microsurgery : user consensus of the European Federation of Societies for Microsurgery
No full textThis study provides a comprehensive guide to robotic-assisted microsurgery. Following more than 900 clinical cases in 13 centers, this joint project was initiated to summarize and consent to the user experience. Two robotic systems specifically designed for the needs of open microsurgery received the first certification for clinical application (CE mark) in 2019 and 2020. Since their introduction into clinical application, several European microsurgical centers have implemented these systems, generating user experiences in multiple microsurgical subspecialties. All institutions using the MUSA-2 microsurgical robot (Microsure B.V., Eindhoven, Netherlands) or Symani Surgical System (Medical Microinstruments, Inc., Wilmington, Delaware, US) were invited to join the multicenter project. A modified nominal group technique was applied to answer five major questions regarding current and future indications and developments in open robotic-assisted microsurgery. Steep preclinical and clinical learning curves were characterized. General considerations concerning the two different systems are presented. Specifics for each microsurgical subspecialty are reported. Following two voting rounds, a consensus was reached in three of the five major questions with "lymphatics" being the top indication, "higher precision" being the top benefit, and "automation" being the top long-term goal of robotic-assisted microsurgery. This joint project of all Symani and MUSA-2 users presents clinical cases and the subsequent initial knowledge and experience. Lymphatics as a top indicator and a higher precision as the top benefit point toward the capabilities of robotic-assisted microsurgery in manipulation of smallest structures. Automation may further enhance and simplify robotic procedures in future. This project also provides a comprehensive guide to any institution aiming to introduce such a system for open robotic-assisted microsurgery in future
Differential susceptibility effects of the 5-HTTLPR and MAOA genotypes on decision making under risk in the Iowa gambling task
No full textIntroduction: The interplay between genetic and environmental factors, as explored through studies of gene-environment interactions (cGxE), has illuminated the complex dynamics influencing behavior and cognition, including decision-making processes. In this study, we investigated the differential susceptibility effects of the 5-HTTLPR and MAOA genotypes on decision-making under risk using the Iowa Gambling Task. Methods: Data from 264 participants (138 women, 126 men) aged 18-22 years, from the 2015 wave of the Survey of Adolescent Life in V & auml;stmanland (SALVe Cohort) was analyzed. Participants provided genetic data including the MAOA and 5-HTTLPR genotypes, and completed the Iowa Gambling Task (IGT) to evaluate decision-making behavior. Parent reports, including assessments of positive parenting styles and early life stress were used for cGxE analysis. Results: In a General Linear Model, significant interactions were found among males for the 5-HTTLPR, with SS/SL carriers showing higher net scores with positive parenting and lower scores with less positive parenting in relation to decision-making under risk in the IGT (trials 61-100), indicating differential susceptibility effects. Male LL carriers showed minimal fluctuation in IGT scores. Similar effects were observed for males with the MAOA S-allele. No significant interactions were found for females. Discussion: In conclusion, our study indicates that the 5-HTTLPR and MAOA genes demonstrate susceptibility to environmental factors in influencing decision-making under risk among males, as assessed by the Iowa Gambling Task. We anticipate that these findings will contribute to advancing the understanding of the complex interactions between genetic and environmental factors in shaping human behavior and decision-making
Developing practices for FAIR and linked data in Heritage Science
No full textHeritage Science has a lot to gain from the Open Science movement but faces major challenges due to the interdisciplinary nature of the field, as a vast array of technological and scientific methods can be applied to any imaginable material. Historical and cultural contexts are as significant as the methods and material properties, which is something the scientific templates for research data management rarely take into account. While the FAIR data principles are a good foundation, they do not offer enough practical help to researchers facing increasing demands from funders and collaborators. In order to identify the issues and needs that arise "on the ground floor", the staff at the Heritage Laboratory at the Swedish National Heritage Board took part in a series of workshops with case studies. The results were used to develop guides for good data practices and a list of recommended online vocabularies for standardised descriptions, necessary for findable and interoperable data. However, the project also identified areas where there is a lack of useful vocabularies and the consequences this could have for discoverability of heritage studies on materials from areas of the world that have historically been marginalised by Western culture. If Heritage Science as a global field of study is to reach its full potential this must be addressed
The dynamics of plasmon-induced hot carrier creation in colloidal gold
No full textThe generation and dynamics of plasmon-induced hot carriers in gold nanoparticles offer crucial insights into nonequilibrium states for energy applications, yet the underlying mechanisms remain experimentally elusive. Here, we leverage ultrafast X-ray absorption spectroscopy (XAS) to directly capture hot carrier dynamics with sub-50 fs temporal resolution, providing clear evidence of plasmon decay mechanisms. We observe the sequential processes of Landau damping (similar to 25 fs) and hot carrier thermalization (similar to 1.5 ps), identifying hot carrier formation as a significant decay pathway. Energy distribution measurements reveal carriers in non-Fermi-Dirac states persisting beyond 500 fs and observe electron populations exceeding single-photon excitation energy, indicating the role of an Auger heating mechanism alongside traditional impact excitation. These findings deepen the understanding of hot carrier behavior under localized surface plasmon resonance, offering valuable implications for applications in photocatalysis, photovoltaics, and phototherapy. This work establishes a methodological framework for studying hot carrier dynamics, opening avenues for optimizing energy transfer processes in nanoscale plasmonic systems
A clinical prostate biopsy dataset with undetected cancer
No full textProstate cancer is a heterogeneous disease showing variability both among individuals and within a patient. While most cases are indolent, aggressive tumors require early intervention. Accurately predicting tumor behavior is challenging, contributing to overdiagnosis but also undertreatment. Current imaging methods may miss the most malignant areas, leading to biopsies often capturing non-malignant prostate tissue even if cancer is present elsewhere in the organ. This non-malignant tissue, however, holds potential as a source for novel diagnostic and prognostic markers. Our clinical dataset comprises men with raised prostate-specific antigen but whose initial prostate needle biopsies only contained benign tissue. Half of the paired patients remained cancer-free for over eight years, while the others were diagnosed with prostate cancer within 30 months of follow-up. We share these initial benign biopsies to enable the exploration of morphological changes in non-malignant tissue and the potential for improved diagnostic accuracy in the early identification of patients with prostate cancer