Publikationer från Uppsala Universitet
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PCET-mediated deconstructive cross-coupling of aliphatic alcohols
No full textA practical deconstructive arylation of aliphatic alcohols has been developed using a synergistic photoredox proton-coupled electron transfer (PCET) and nickel dual catalytic system. The method efficiently generates alkyl radicals via concerted PCET-mediated beta-scission, enabling the formation of C(sp3)-C(sp2) bonds between alcohols and aryl halides. Optimization studies revealed a broad functional group tolerance and high chemoselectivity, with good yields even for challenging tertiary alcohol substrates. Mechanistic insights from transient absorption spectroscopy confirmed the dominance of a PCET pathway for radical generation. This strategy expands the utility of alcohols as alkyl radical precursors in cross-coupling reactions, offering a versatile tool for constructing complex molecular architectures
Evidence of Site-Specific Mucosal Autoantibody Secretion in Rheumatoid Arthritis
No full textObjective Anti–citrullinated protein antibodies (ACPA) have been detected in sputum and saliva, indicating that anti–modified protein antibodies (AMPA) can be produced at mucosal sites in patients with rheumatoid arthritis (RA). However, the body's largest mucosal compartment, the gut, has not yet been examined. We therefore investigated the presence of several AMPA (ACPA, anti–carbamylated protein antibodies [anti-CarP], and anti–acetylated protein antibodies [AAPA]) at different mucosal sites, including the intestinal tract. Methods Paired fecal/ileal wash, saliva, and serum samples of patients with RA and healthy volunteers were collected in two independent cohorts. Data involving feces were replicated in a third cohort. In these secretions, AMPA were analyzed using in-house enzyme-linked immunosorbent assay with unmodified peptides as control. In fecal samples, total IgA and anti–Escherichia coli IgA were measured. Results ACPA, anti-CarP, and AAPA IgA were measurable in saliva of seropositive patients with RA (prevalence 9%–40%). No AMPA could be detected in feces. IgA was present because total IgA and anti–E. coli IgA were detectable in feces of ACPA-positive patients with RA and healthy donors. Results were confirmed in another cohort using colonoscopically collected ileal wash samples. Conclusion Our study shows the presence of ACPA, anti-CarP, and AAPA IgA in saliva of ACPA-seropositive patients with RA. However, no AMPA could be detected in feces/ileal wash samples of these patients, although our assays were able to measure other antigen-specific antibodies. These data suggest that mucosal autoantibody secretion may occur in the oral mucosa of patients with RA, whereas no evidence could be found for this process in the lower gastrointestinal tract
Boswellia hesperia sp. nov. (Burseraceae) from Socotra
No full textThe new species Boswellia hesperia Thulin, M.H.Weber and Rzepecky is described, illustrated and mapped. It is a dwarf tree, restricted to westernmost Socotra (Yemen), growing on limestone rocks, in which the usually prostrate stems tend to fill out holes and crevices. It differs from B. nana Hepper, another dwarf tree endemic to Socotra but restricted to the easternmost parts of the island, by having leaves densely pubescent with whitish hairs beneath and by its smaller flowers and fruits
Computational fluid dynamics of hot and cold air flow inside short and long mixing tees
No full textIn this paper, the numerical simulation was done for a cylindrical tee by establishing a steady-state simulation to examine the mixing performance. The temperature of the fluid at the hot inlet was chosen as 36 °C and 19 °C for the cold inlet. The numerical simulation was done for a short tee of 192 mm and a long mixing tee of 262 mm at a variety of momentum ratios. The geometry was meshed in FLUENT before solving the domain. For the meshing, the faces were initially named hot inlet, cold inlet, outlet, and walls. The triangular method was chosen to generate a mesh for the flow domain. The size of the cell in meshing was taken as 0.1 m. In this work, the SST k–ω models were selected to perform the computations. The analytical values of temperature were used to validate the numerical results. Results show that the thermal mixing was done effectively using the CFD ANSYS software package. Results show that the size of the mixing area is the same hence there is not much of a difference between the long tee and the short tee in that particular sector. The thermal mixing was found better when the velocity at the vertical inlet (y-axis) becomes greater and the average temperature is lower. Also, the increase in the pipe's length causes the average temperature to drop since the fluid mixes better the farther along it travels, while also slightly increasing the velocity
Computational fluid dynamics of flow over a cylindrical tube for steady and transient flow conditions
No full textThe primary objective of this numerical study is to analyse the 2D flow across a circular cylindrical tube under various laminar as well as turbulent flow regimes. In this study, the implicit finite volume scheme was employed to compute incompressible flow with time precision using convective flux discretization schemes of the second order. The computational results were validated by comparing the simulation results with empirical data of mean surface pressure, wake characteristics in both constant and transient flow regimes, and the Strouhal frequency associated with vortex scattering. In addition, the present simulation model adequately captures the intricate 2D flow structure of the cylinder wake
Income and education affect prognosis and treatment in symptomatic myeloma
No full textDespite advancements in multiple myeloma treatment, prognostic variability persists. We investigated the impact of income and education on treatment and survival in a country with publicly funded healthcare. We analysed data from the Swedish Myeloma Registry (2008–2021) linked to national registers. Cox models assessed survival, adjusting for demographics and comorbidities. Treatment patterns were compared using cumulative incidence functions. Among 8,672 patients, higher education and income correlated with prolonged survival. Adjusted hazard ratios (HRs) for low income were 1.4 (95% CI 1.3–1.5) and for low education were 1.3 (95% CI 1.2–1.4). Higher income patients were more likely to receive lenalidomide (HR 1.5, 95% CI 1.3–1.6) and pomalidomide (HR 1.7, 95% CI 1.4-2.0), and less likely to receive melphalan tablets (HR 0.8, 95% CI 0.7–0.9). Low-income patients were less likely to undergo stem cell transplant (HR 0.8, 95% CI 0.7–0.9). Immigrant status or biological sex did not influence outcomes. Even in a tax-funded system, socioeconomic disparities impact myeloma survival and treatment. Lower socioeconomic status correlates with inferior outcome and more conservative treatment. Attitudinal biases may contribute to these disparities. Better treatment for the less privileged patients could significantly improve myeloma survival, advocating for efforts to overcome the influence of socioeconomic status
Narrating and Translating Medea in Medieval Romances : Narrative Strategies in Greek, Medieval Latin, and Middle High German Translations of the Roman de Troie
No full textTroponin I is an independent predictor of cardiovascular events and mortality in haemodialysis patients
No full textBackground: Patients with end-stage kidney disease (ESKD) undergoing haemodialysis (HD) have a high risk of cardiovascular (CV) events. This study evaluated troponin I (hs-cTnI) as a predictor of major adverse cardiac events (MACEs), CV death and all-cause death. Methods: The AURORA trial, a multicentre, randomized, double-blind trial involved 2776 HD patients comparing rosuvastatin with placebo. No significant effect was found on the composite primary endpoint of CV death, non-fatal myocardial infarction or non-fatal stroke. In this post hoc analysis, we analysed the association between baseline hs-cTnI and outcomes using Cox regression analyses. We adjusted for multiple background factors and available biomarkers. Hs-cTnI was log2-transformed and modelled using a four-knot restricted cubic spline. Variables were ordered by their importance in the models using chi 2 value minus degrees of freedom. Results: Baseline median hs-cTnI was 17.3 pg/mL. During follow-up, 734 MACEs, 598 CV deaths, and 1094 total deaths occurred. Patients in the upper quartile of hs-cTnI (>32.6 pg/mL) had significantly higher risk of MACEs [hazard ratio (HR) 1.92; 95% confidence interval (CI) 1.57-2.35], CV death (HR 2.12; 95% CI 1.69-2.66), all-cause death (HR 1.84; 95% CI 1.55-2.17) and non-CV death (HR 1.59; 95% CI 1.23-2.05) after full adjustment compared with those in the lowest quartile (<10.1 pg/mL). Hs-cTnI was identified as the strongest predictor for MACEs, CV death, and all-cause death, but not for non-CV death. Conclusions: Baseline hs-cTnI is a strong and independent predictor for MACEs and death in patients with ESKD undergoing haemodialysis
Isolated Grid-Forming Control of Wave Energy Converter for Island Electrification
No full textAs the world transitions to renewable electrification to reduce CO2 emissions, remote island electrification remains a challenge. Although some islands are connected to the grid, many still rely on fossil fuels for electricity generation. Several studies indicate that renewable energy sources, such as wave energy, have the potential to make these islands self-reliant because of their substantial power potential. However, research on the control of power electronics converters for these systems remains limited. This paper proposes isolated grid-forming control for island electrification to address this gap using a wave energy converter and an energy storage system. Resistive loading control is implemented to optimize the power absorption of the generator. The result illustrates the establishment of the required AC voltage and 50 Hz frequency in the island load, ensuring harmonics compliance with the recommended standards. Experiments were conducted to test and validate the operation of different converter controls. The results also demonstrate the converter's ability to black-start the island load and automatically transition the load current with varying loads in a few milliseconds. Furthermore, the power quality produced by the wave energy converter presents one of its significant challenges. Therefore, the performance of two distinct converter technologies was compared. The performance of the IGBT converter was evaluated against that of the SiC-based converter in terms of power quality. The study demonstrates that the use of SiC enhances power quality in all switching frequencies tested, achieving the most significant reduction of 78% in current THD and 92% in voltage THD at the 25 kHz switching frequency, thus validating its advantages for wave energy converter applications
Advances in posterity of visualization in paradigm of nano-level ultra-structures for nano-bio interaction studies
No full textThe progression in contemporary scientific field is facilitated by a multitude of sophisticated and cutting-edge methodologies that are employed for various research purposes. Among these methodologies, microscopy stands out as a fundamental and essential technique utilized in scientific investigations. Moreover, due to the continuous evolution and enhancement of microscopic methodologies, nanotechnology has reached a highly developed stage within modern scientific realm, particularly renowned for its wide-ranging applications in the fields of biomedicine and environmental science. When it comes to conducting comprehensive and in-depth experimental analyses to explore the nanotechnological aspects relevant to biological applications, the concept of nano-biological interaction emerges as the focal point of any research initiative. Nonetheless, this particular study necessitates a meticulous approach toward imaging and visualization at diverse magnification levels to ensure accurate observations and interpretations. It is widely acknowledged that modern microscopy has emerged as a sophisticated and invaluable instrument in this regard. This review aims to provide a comprehensive discussion on the progress made in microscopic techniques specifically tailored for visualizing the interactions between nanostructures and biological entities, thereby facilitating the exploration of the practical applications of nanotechnology in the realm of biological sciences