Publikationer från Uppsala Universitet
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Enhanced glomerular thrombosis in pronated animals with ARDS
No full textBackground: Prone positioning is part of the management of acute respiratory distress syndrome (ARDS) and has been demonstrated to successfully improve the ventilation-perfusion match and reduce mortality in patients with severe respiratory failure. However, the effect of pronation on other organs than the lungs has not been widely studied. This study aimed to compare abdominal edema, perfusion and inflammation in supine and prone positioning in a porcine ARDS model. Methods: Seventeen piglets were randomized into two groups: a supine group (n = 9) and a prone group (n = 8). Both groups received endotoxemic infusion and were observed for 6 h. Three animals per group underwent positron emission tomography-magnetic resonance imaging (PET-MRI) for imaging acquisition. Hemodynamic and respiratory parameters were recorded throughout the protocol. Inflammation was assessed by measuring cytokine concentrations in blood, ascites and the abdominal organs' tissue. The edema in abdominal organs was assessed by wet-dry ratio and pathophysiological analysis of tissue samples and by MRI and PET measurements from volumes of interest (VOIs) delineated in abdominal organ in MRI and PET images. The abdominal organs' perfusion was also assessed by MRI and PET measurements. Results: The prone group had a faster CO2 washout and needed a lower positive end-expiratory pressure to maintain the desired oxygenation. In the prone group duodenal edema was lower (measured with wet-dry ratio) and renal perfusion, by both MRI and PET measurements, was lower than half compared to the supine group (MRI, perfusion fraction, f: supine group 0.13; prone group 0.03; p-value 0.002. PET Flow: supine group 1.7; prone group 0.4 ml/cm3/min; p-value 0.002). In addition, the histopathological samples of the kidneys showed a higher incidence and extent of glomerular thrombosis in the prone group. Conclusions: In a porcine ARDS model, prone positioning was associated with enhanced glomerular thrombosis and low renal perfusion
Czas otwarcia Iapetusa i tego konsekwencje dlazrozumienia rozpadu Rodinii i ewolucji Baltiki:spostrzeżenia z Kaledonidów Skandynawskich icentralnej Polski
No full textPlate tectonics as a simple concept can be summarized as follows: a supercontinent breaks up and different portions of it are driven apart from one another forming new oceans. Eventually, the continents will merge again closing the ocean between them. This cycle is called the “Wilson Cycle”. While the basic concept of a Wilson Cycle is well accepted, the specifics of the timing and dynamics of continental break up often remain mysterious. This PhD project aims to determine precisely when the Iapetus Ocean formed following the break-up of the ancient continent Rodinia. Additionally, this PhD thesis investigates the evolution of Baltica, one of the continents formed by the separation of Rodinia. In order to achieve these goals, several methods are applied to rocks collected from different localities. Metaigneous rocks were collected from the northern part of the Swedish Caledonides and constitute the samples for Chapter 1 and 2. These rocks are related to igneous activity associated with continental break-up and opening of the Iapetus Ocean and were subsequently metamorphosed during the later stage of the Wilson Cycle, when subduction and collision of Baltica with Laurentia formed the Caledonian Orogeny. Chapter 3 investigates (meta)sedimentary rocks from the Holy Cross Mts. in southwestern Poland. They record evidence of the break-up and rifting, because they represent a portion of the paleo-southwestern margin of Baltica and record information about Baltica’s evolution through time. In terms of analytical techniques, the PhD project started with classical petrological investigation using a microscope, chemical characterization of minerals using electron microprobe (EMP), whole-rock major and trace element geochemistry, geochronology (U-Pb monazite and zircon and 39Ar/40Ar white mica), conventional and trace element geothermobarometry and phase equilibria modelling. The new data collected in this PhD project provide new insights into the Neoproterozoic–Cambrian Iapetus Ocean rifting and break-up of Rodinia. Specifically, the discoveries include evidence of a failed rifting episode in the supercontinent Rodinia (Chapter 1), geochronological and geochemical data for the igneous activity during the actual rifting (Chapter 2), and the definition of a convergent margin setting for the southwestern Baltica margin during the middle Cambrian (Chapter 3)The following PhD dissertation was conducted as a Double Degree between Uppsala University (Sweden) and AGH University of Krakow (Poland). According to the contract, the thesis was designed according to the template in use at AGH University of Krakow. The thesis at AGH University do not have an ISSN/ISBN number.</p
Raising the Floor? : Genetic Influences on Educational Attainment Through the Lens of the Evolving Swedish Welfare State
No full textInterest in the role of genetics in influencing key life outcomes such as educational attainment has grown quickly. However, the question of whether genetic influences on educational attainment, on average as well as in conjunction with socioeconomic circumstances, are moderated by macro-level factors has not yet received sufficient attention. This study combines polygenic indices for educational attainment (EA PGI) with high-quality register data in a large sample of Swedish twins of European ancestry born 1920–1999. Employing both conventional between-family and within-family models, the analyses suggest that the influences of education-related genetic propensities on educational attainment have increased in Sweden during the twentieth century, a period featuring major expansions of the Swedish educational system, and decreasing economic inequality. The analyses also suggest that the degree to which socioeconomic background enhances genetic influences on education has decreased across cohorts. Genetic influences on education do not appear to have translated into increased genetic influences on income. Additionally, there is some evidence of floor and ceiling effects in the analyses of dichotomous educational outcomes
Euclid preparation : LX. The use of HST images as input for weak-lensing image simulations
No full textData from the Euclid space telescope will enable cosmic shear measurements to be carried out with very small statistical errors, necessitating a corresponding level of systematic error control. A common approach to correct for shear biases involves calibrating shape measurement methods using image simulations with known input shear. Given their high resolution, galaxies observed with the Hubble Space Telescope (HST) can, in principle, be utilised to emulate Euclid observations of sheared galaxy images with realistic morphologies. In this work, we employ a GalSim-based testing environment to investigate whether uncertainties in the HST point spread function (PSF) model or in data processing techniques introduce significant biases in weak-lensing (WL) shear calibration. We used single Sersic galaxy models to simulate both HST and Euclid observations. We then 'Euclidised' our HST simulations and compared the results with the directly simulated Euclid-like images. For this comparison, we utilised a moment-based shape measurement algorithm and galaxy model fits. Through the Euclidisation procedure, we effectively reduced the residual multiplicative biases in shear measurements to sub-percent levels. This achievement was made possible by employing either the native pixel scales of the instruments, utilising the Lanczos15 interpolation kernel, correcting for noise correlations, and ensuring consistent galaxy signal-to-noise ratios between simulation branches. Alternatively, a finer pixel scale can be employed alongside deeper HST data. However, the Euclidisation procedure requires further analysis on the impact of the correlated noise, to estimate calibration bias. We found that additive biases can be mitigated by applying a post-deconvolution isotropisation in the Euclidisation set-up. Additionally, we conducted an in-depth analysis of the accuracy of TinyTim HST PSF models using star fields observed in the F606W and F814W filters. We observe that F606W images exhibit a broader scatter in the recovered best-fit focus, compared to those in the F814W filter. Estimating the focus value for the F606W filter in lower stellar density regimes has allowed us to reveal significant statistical uncertainties
Body mass index trajectories from birth to early adulthood and lung function development
No full textBACKGROUND: Limited studies have investigated the influence of body mass index (BMI) trajectories on lung function covering the entire growth period. METHODS: We conducted a prospective study utilizing data from the Swedish BAMSE birth cohort. Latent class mixture modelling was employed to examine the diversity in BMI z-scores from birth to 24 years of age. Participants with four or more BMI z-scores were included (n=3204, 78·4%). Pre-bronchodilator (BD) spirometry was tested at 8, 16, and 24 years, while post-BD spirometry, multiple-breath nitrogen washout (for lung clearance index, LCI), and urinary metabolomics data were assessed at 24 years. RESULTS: Six distinct BMI development groups were identified. Compared to the stable normal BMI group, the accelerated increasing BMI group exhibited reduced pre- and post-BD FEV1/FVC ratio z scores (β=-0·26, 95% CI=[-0·44, -0·08], and -0·22, [ -0·39, -0·05], respectively), along with elevated LCI (0·30, [0·22, 0·42]) at 24 years. The persistent high BMI group demonstrated lower FEV1, and FVC z scores growth between 16 and 24 years (-0.24, [-0.42, -0.05], and -0.27, [-0.45, -0.01], respectively), and elevated LCI (0·20, [0·03, 0·39]) at 24 years. However, those impairments were not observed in the accelerated resolving BMI group. Conversely, the persistent low BMI group displayed persistently decreased FEV1, and FVC from 8 to 24 years, as well as decreased lung function growth. Additionally, histidine-related metabolites were associated with pre- and post-BD FEV1 (hypergeometric FDR=0.008 and <0.001, respectively). CONCLUSIONS: Early interventions aiming for normal BMI during childhood may contribute to improved lung health later in life
Guinier-Preston zone hardening during vacuum annealing of (Ti1-xAlx)0.92W0.08N (0.07 ≤ x ≤ 0.79) thin films
No full textWe present a systematic study on the formation of Guinier-Preston (GP) zones and corresponding age hardening in metastable cubic (Ti1-xAlx)0.92W0.08N thin films at annealing temperatures relevant to cutting tool applications. The Al content, which determines the compound's phase stability, varies widely from x = 0.07 to 0.79. The density of GP zones forming after 2 h long annealing in vacuum at 950 °C is assessed by cross-sectional transmission electron microscopy. Concurrent to the spinodal decomposition of c-(Ti,Al,W)N into c-Ti(W)N and c-Al(W)N, tungsten forms atomic-plane-thick W disks on (111) planes of the cubic matrix. The density of GP zones is ∼ 6.3·1011 – 1.2·1012 cm−2 in the 0.07 ≤ x ≤ 0.58 range and decreases to 1.8·1011 cm−2 with х = 0.65 concomitant with precipitation of w-AlN grains and bcc-W nanocrystallites. GP zone formation and age hardening is observed for all films with 0.07 ≤ x ≤ 0.58 with 2 to 14 % increase in hardness, starting from high levels between 23.5 and 32.9 GPa. Elevated hardness is, thus, retained over the entire temperature range: 520 to 950 °C. Finally, precipitation of bcc-W at х ≥ 0.65 during annealing above 950 °C is observed as a means to relax misfit strain between the c-Ti(W)N and w-Al(W)N components
Some homological properties of category O, VII
No full textWe describe Calabi-Yau objects in the regular block of the (parabolic) BGG category O associated to a semi-simple finite dimensional complex Lie algebra. Each such object comes with a natural transformation from the Serre functor to a shifted identity whose evaluation at that object is an isomorphism
Structure and function of the geldanamycin amide synthase from Streptomyces hygroscopicus
No full textAmide synthases catalyze the formation of macrolactam rings from aniline-containing polyketide-derived seco-acids as found in the important class of ansamycin antibiotics. One of these amide synthases is the geldanamycin amide synthase GdmF, which we recombinantly expressed, purified and studied in detail both functionally as well as structurally. Here we show that purified GdmF catalyzes the amide formation using synthetically derived substrates. The atomic structures of the ligand-free enzyme and in complex with simplified substrates reveal distinct structural features of the substrate binding site and a putative role of the flexible interdomain region for the catalysis reaction
Magnetic structure of Mn2GaC thin film by neutron scattering
No full textMAX phases are a family of atomically laminated materials with various potential applications. Mn2GaC is a prototype magnetic MAX phase, where complex magnetic behaviour arises due to competing interactions. We have resolved the room temperature magnetic structure of Mn2GaC by neutron diffraction from single-crystal thin films and we propose a magnetic model for the low temperature phase. It orders in a helical structure, with a rotation angle that changes gradually between 120 degrees and 90 degrees depending on temperature
Zsófia Torma and the cradle of civilisation : Transylvania's pioneering archaeologist and her discoveries
No full textMore than 7000 years ago, parts of central and south-eastern Europe were already home to advanced agricultural societies, with city-like settlements housing several thousand inhabitants. The first traces of this remarkable culture were excavated in the 1870s at Tordos (Turdaș) in Transylvania, by Zsófia Torma (1832–1899), Hungary’s first female archaeologist and one of the very first women in the history of archaeology. This book is about this remarkable woman and her discovery – the traces of Europe’s first civilisation, with the oldest traces of metallurgy to date and possibly even a form of early writing. The book also describes the place where Zsófia Torma worked, Hungarian Transylvania, and its history. Her life’s work coincides with a very important period in Hungarian history, in a Europe that would soon be shattered by the carnage of the First World War. Archaeology was a new science, and Zsófia was one of its very first women. She should therefore be well known in the history of archaeology, which is unfortunately not the case. It is therefore time to bring her to light, as well as the Transylvania that shaped her and the outstanding archaeological discoveries she made.