Publikationer från Umeå universitet
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Gender biases in surgical residency and their association with postoperative outcomes : a qualitative study of residents in general and orthopedic surgery
No full textObjectives: Recent studies have shown gender-based disparities in surgical outcomes, with women physicians achieving better postoperative results. However, the mechanisms underlying these differences remain poorly understood. This complex, underexplored phenomenon lacks perspectives from key stakeholders such as patients, staff, and surgeons. Surgical residents inhabit a unique position, balancing the roles of learners and healthcare providers and offering valuable insights into these disparities. Our objective was to explore resident surgeons' perceptions of the mechanisms underlying the differences observed in postoperative outcomes through interviews. Methods: We conducted a qualitative study using semi-structured interviews with men and women residents, analyzed through qualitative content analysis. Participants included 17 surgical residents from 10 ACGME-accredited orthopedic and general surgery programs across four U.S. regions. Results: Key findings were: (1) Women surgical residents experienced gender biases during training; (2) Men and women surgeons differed in their approaches to patient care and surgical practice. Residents of both genders noted that women surgeons encounter biases stemming from prevailing norms, beliefs, and expectations related to gender. These biases manifest as double standards and pressure to conform to men-dominated environments. The absence of comparable pressure on men surgeons to adapt to interactions with women colleagues or patients may lead to challenges in meeting the expectations of women patients. Participants of both genders reported that women surgeons tend to adopt a more holistic approach to patient care. Conclusions: Our findings suggest that the unique challenges faced by women surgeons may contribute to the development of refined interpersonal and surgical skills, which could be associated with improved postoperative outcomes. Raising awareness of gender-based differences in surgical practice is essential to addressing the disparities observed in postoperative results. Practical Implications: Residency programs may benefit from incorporating gender-aware training to address implicit biases, foster equitable learning environments, and optimize skill development for all trainees
Vaccine protection against COVID-19 mortality in relation to time since last booster dose among nursing home residents in Sweden : A case-control study over 35 months
No full textBackground: The implementation of COVID-19 vaccination among older persons at nursing homes has lowered the infection-associated mortality considerably, but emerging virus variants and decline in vaccine-induced immunity over time necessitate examination of future booster dosing strategies. The overall aim of this study was to assess vaccine protection against COVID-19 mortality in relation to time elapsed since the last booster dose. Methods: All older persons living in nursing homes in Sweden at any time point December 27th, 2020 - December 4th, 2023 were included. For each case (5256 COVID-19 and 85,745 all-cause deaths), up to 10 controls were sampled randomly from this population, matched with respect to birth year, sex and county. The matched case-control sets were analyzed for vaccination history with conditional logistic regression, with further adjustment for co-morbidties and prior SARS-CoV-2 infection. Findings: Vaccination status (unvaccinated vs. vaccinated), ≥ 90 days since last vaccine dose, a co-morbidity score ≥ 2, and no previous SARS-CoV-2 infection were associated with death occurring within 30 days of a positive test. The odds ratio (OR) for COVID-19 death was 2.4 (95 % confidende interval [CI] 1.8–3.2) when contrasting at least 365 days with less than 90 days since the last vaccine dose. Interpretation: Waning vaccine protection was observed already 90 days after the last vaccine dose among older people living in nursing homes. The reported ORs imply that more than one third of all COVID-19 deaths could in the investigated setting have been possible to prevent by more frequent vaccine boosting during 2022–2023
Balancing grazing and biodiversity : arthropod responses to modern cattle farming practices
No full textRuminant production exerts severe pressure on ecosystems through land use change for pasture and fodder production, contributing to biodiversity loss, disruption of natural biogeochemical fluxes, and climate change. Whereas ruminant production can support biodiversity that has co-evolved with grasslands and grazing animals, the values of temporary grasslands are poorly understood. In this study, we assessed the effects of grazing regimes practised on modern cattle farms, including no grazing, on the abundance, biomass, and taxonomic richness of aerial and ground-dwelling arthropods. We assessed the potential value of organic management compared to grazing on conventional farms, and the role of vegetation structure on the pastures. We sampled arthropods in temporary pastures and silage grasslands, spring cereal fields, and in farmyards on 43 dairy and suckler cow farms in Finland. We show that grazing benefits the richness of ground-dwelling arthropods in fields, and the benefits were most evident at extensive levels of grazing at the farm scale. Grazing had no significant benefits for the biomass of ground-dwelling arthropods or relative abundance of aerial arthropods over field vegetation. Grazed rotational grasslands had similar levels of arthropods as mown grasslands or cereal crops, except for a higher richness of ground-dwelling arthropods. Taxonomic richness of ground-dwelling arthropods was higher on organic farms than conventional, but only at low grazing intensities. Although our study suggests several ways in which livestock farmers can maintain and increase arthropod populations on their farms, these may be associated with some reduction in production output on modern farms oriented towards high yields
Spectral and stiffness characterization of whole prostate gland to assist superficial cancer detection during radical prostatectomy
No full textProstate cancer treatment depends on whether the cancer exists only inside the gland or within the prostate capsule or on the outside surface of the gland. The presence on the outside surface indicates migration of the cancer to adjacent organs. This study presents a novel method for detecting prostate cancer (PCa) on the surface of excised prostate glands using Raman spectroscopy and stiffness measurements. The workflow involves assessing the location and extent of PCa via MRI before surgery, followed by 3D scanning of the excised prostate. Key positions on ten excised prostates, 211 positions with 56 deemed as cancer, are measured using Raman spectroscopy and stiffness probes. The results are mapped onto a digital representation of the prostate to aid surgical decision-making. Statistical analysis of the Raman data indicates that spectra could be divided into two components, one more related to cancer and one more related to normal tissue. A stiffness parameter was calculated from resonance measurements from the stiffness probe. The Raman components and stiffness parameters were converted to z-scores. Logistic generalized linear mixed modelling revealed that the stiffness parameter was statistically associated with cancer presence in prostate regions (p = 0.009). The scanning equipment is easy to handle and makes further larger studies possible. This method holds promise for providing real-time support during surgery, reducing the need for post-surgical therapies and minimizing patient distress
Interactions between litter-feeders and the burrowing earthworm A. caliginosa do not affect mineral-associated C addition in recent spoil material
No full textSoil macrofauna affects litter decomposition by modifying organic matter availability for microorganisms. Litter-feeders accumulate partially decomposed organic matter at the soil surface, while burrowing earthworms mix the organic matter with mineral particles. Synergistic effects of the combined presence of litter-feeders and burrowing earthworms through facilitation are expected but seldom tested. We performed a three-months microcosm experiment in which we tested the effect of the presence of litter-feeders (an epigeic earthworm and an isopod) on the biomass of the burrowing earthworm Aporrectodea caliginosa and on C incorporation into individual soil organic matter fractions. We used a recent post mining soil, limited in food resources to promote interactions, and alder litter which is suitable food for soil invertebrates. We hypothesized that A. caliginosa would be positively affected by the presence of litter feeders, and that this would impact C addition to the more stable fractions. Contrary to our hypotheses, we found no variation in the biomass of A. caliginosa among treatments, as this species could feed directly on alder leaves. The accumulation of poorly stabilized particulate organic C was negatively affected by the presence of both earthworm species (i.e. less than cumulative), suggesting either that A. caliginosa fed on the particulate organic matter produced by the epigeic earthworm, or that competition for the limiting food resources took place. However, A. caliginosa promoted a similar increase in stable mineral-associated C in all treatments. This confirms the plasticity of A. caliginosa regarding food resources observed in other experiments, and shows that the effect of the burrowing earthworm A. caliginosa on stable C accumulation is not necessarily mediated by litter-feeders in the presence of litter of good quality
Low-oxygen freshwaters as ecological niches for mercury methylators
No full textMethylmercury (MeHg) is a hazardous neurotoxin, predominantly formed by microbial transformation of inorganic mercury in oxygen-depleted aquatic and terrestrial ecosystems. The ongoing deoxygenation of aquatic ecosystems due to global warming is likely to expand microbial niches for MeHg production. Although mercury methylators have also been reported to thrive in oxyge-deficients conditions in a few marine and freshwater ecosystems, there is a lack of comprehensive understanding of how they are distributed in freshwater systems. In this study, we retrieved hgcA genes, genomic marker for mercury methylation potential, from 586 metagenomes from the water column of 186 freshwater systems. Overall, hgcA genes were detected in the water column of 30 lakes, with the highest richness and abundance being detected in anoxic (0 mg O2L-1) and hypoxic (>0–2 mg O2L-1) compared to oxic conditions (>2 mg O2L-1). Although Desulfobacterota had the highest hgcA gene richness across most freshwater systems, certain systems were dominated by hgcA genes from Bacteroidales and Kiritimatiellales, implying metabolic and ecological versatility of mercury methylators as a group. Our findings suggest that projected expanding deoxygenation may lead to new niches for mercury methylators in inland waters
Enabling mixed-precision in spectral element codes
No full textMixed-precision computing has the potential to significantly reduce the cost of exascale computations, but determining when and how to implement it in programs can be challenging. In this article, we propose a methodology for enabling mixed-precision with the help of computer arithmetic tools, roofline model, and computer arithmetic techniques. As case studies, we consider Nekbone (Nek5000 developers), a mini-application for the Computational Fluid Dynamics (CFD) solver Nek5000 (Fischer et al.), and a modern Neko (Jansson et al., 2024) CFD application. With the help of the Verificarlo (Denis et al., 2016) tool and computer arithmetic techniques, we introduce a strategy to address stagnation issues in the preconditioned Conjugate Gradient method in Nekbone and apply these insights to implement a mixed-precision version of Neko. We evaluate the derived mixed-precision versions of these codes by combining metrics in three dimensions: accuracy, time-to-solution, and energy-to-solution. Notably, mixed-precision in Nekbone reduces time-to-solution by roughly 1.62x and energy-to-solution by 2.43x on MareNostrum 5, while in the real-world Neko application, the gain is up to 1.3x in both time and energy, with the accuracy that matches double-precision results
Greater increase in surface albedo following clear-cutting than wildfire in pine dominated northern Swedish boreal forests
No full textThere is a public debate on how boreal forests can deliver climate change mitigation benefits. While most debates regarding Fennoscandian forests have centered on the contrasting effects of actively managed and old-growth unmanaged forests on carbon uptake and storage, the impact of surface albedo has often been overlooked. According to the new EU forest strategy for 2030, with aim of improving quantity and quality of forests by promoting primary old-growth forests and avoiding clear-cutting, among others, we examined how albedo across a wide age range of boreal Pinus-dominated forests develops over time after wildfire (defined as unmanaged) and clear-cutting (defined as managed). We find that albedo decreases over time after disturbance, but mainly in managed forests. Annual mean albedo in young (<30 years) managed forests (0.36±0.04) is markedly larger than in young unmanaged forests (0.18±0.04). This difference is particularly prominent during winter, when snow-covered ground is present. The mean albedo over the entire unmanaged forest-age gradient (0.17±0.05) is significantly lower (p < 0.05) than that of the managed forest-age gradient (0.23±0.10). Considering the typically higher frequency of clear-cuts compared to wildfires in Fennoscandian forests, these albedo differences would be even larger over long time scales. Our findings reveal the importance of considering the climatic cooling potential of albedo when making decisions on how to optimize future forest management in northern boreal forests to mitigate climate change
Position specific isotope analysis of diethylamine by 2H and 13C NMR : dual nucleus analysis in forensic investigation of illegal use of chemical weapons
No full textDiethylamine (DEA) is a known precursor to some of the most toxic chemical warfare agents (CWA) as both V-agents and Fourth Generation Agents (FGAs) contain the dialkylamine functionality. DEA is also a readily available commercial substance with extensive use in the chemical industry for legitimate purposes. Because of this potential dual use, it is desirable to develop methods to trace the origin of dialkylamines if they are used for illicit purposes. We herein demonstrate that it is possible to differentiate six commercial batches of DEA using position-specific isotope analysis (PSIA) by both 2H and 13C NMR. Using a high-field NMR spectrometer together with a cryogenic 2H probe, we have produced 2H-{1H} NMR data with high accuracy and precision. The PSIA by NMR results show that the intramolecular 2H ratios of all six DEAs are significantly different while two of the six DEAs have unique 13C ratios. Further, the intramolecular isotopic variations can be used to link the DEAs to different suppliers. The two nuclei separately contribute to isotopic profiles of the DEAs. However, combining the two techniques provides a higher-resolved isotopic profile that can differentiate all DEAs and thus be useful in forensic investigations of illegal use of chemical weapons
Interrater, test-retest, and intersession reliability of a test designed to measure tibialis posterior strength with a hand-held dynamometer
No full textBackground: The tibialis posterior muscle has an important role both in stabilizing the foot and in inversion, plantar flexion, and adduction of the foot. Impaired function can lead to tibialis posterior dysfunction. A clinical test that can objectively measure tibialis posterior strength is warranted. Objectives: The aim of this study was to investigate the interrater, test-retest, and intersession reliability of a test designed to measure tibialis posterior strength with a hand-held dynamometer. Design: Interrater, between-day test-retest and intersession reliability. Setting: University laboratory. Participants: The participants comprised 20 healthy individuals (mean age 28.8 years, n = 10 women) without foot problems. Method: A test was designed to test tibialis posterior strength with a hand-held dynamometer (HHD). The test was performed on two occasions 5–15 days apart and was carried out by two raters. The intraclass correlation coefficient (ICC), 95 % confidence interval, standard error of measurement (SEM), and minimal detectable change were calculated. Results: Interrater reliability was good on both occasions (ICC: 0.769, 0.794), test-retest reliability was moderate for both raters (ICC: 0.671, 0.672), and intersession reliability was excellent (ICC: 0.934–0.967). However, the confidence interval had a large variation (-0.027–0.986) and the SEM was relatively high (2.356–3.863 N). Conclusions: This test seems to be reliable, but has some limitations. The results suggest that the current version of the test could be used to compare strength between feet, but that further development of the test is needed to achieve increased interrater and test-retest reliability