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- Axelsson Fisk, Sten, et al.
(författare)
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Social inequalities in the risk of giving birth to a small for gestational age child in Sweden 2010–16 : a cross-sectional study adopting an intersectional approach
- 2024
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Ingår i: European Journal of Public Health. - 1101-1262 .- 1464-360X. ; 34:1, s. 22-28
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Tidskriftsartikel (refereegranskat)abstract
- Background: Well-established associations exist between the risk of small for gestational age (SGA) and unidimensional sociodemographic factors. We investigated social inequalities in SGA risk and adopted an intersectional approach that simultaneously considers different social categories. By doing so, we could assess heterogeneities in SGA risk within unidimensional sociodemographic categories. Methods: We included all live 679 694 singleton births in Sweden between 2010 and 2016. The outcome was SGA, and the exposures were age, maternal educational level, dichotomous migration status and civil status. Thirty-six possible combinations of these factors constituted the exposure in an intersectional model. We present odds ratios (ORs) with 95% confidence intervals (95% CIs) and the area under the receiver operating characteristic curve (AUC)—a measurement of discriminatory accuracy (i.e. the ability to discriminate the babies born SGA from those who are not). Results: Women with low education and women born outside Sweden had ORs of 1.46 (95% CI 1.38–1.54) and 1.50 (95% CI 1.43–1.56) in unidimensional analyses, respectively. Among women aged under 25 with low education who were born outside Sweden and unmarried, the highest OR was 3.06 (2.59–3.63). The discriminatory accuracy was low for both the unidimensional model that included all sociodemographic factors (AUC 0. 563) and the intersectional model (AUC 0.571). Conclusions: The intersectional approach revealed a complex sociodemographic pattern of SGA risk. Sociodemographic factors have a low accuracy in identifying SGA at the individual level, even when quantifying their multi-dimensional intersections. This cautions against interventions targeted to individuals belonging to socially defined groups to reduce social inequalities in SGA risk.
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| 2. |
- Axelsson, Josefine, 1992-
(författare)
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Interglacial climates in proxies and models : Utilizing sampled oxygen isotopes and model simulations to understand past Indian summer monsoon variability
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The study of Earth's climate system, including the mechanisms driving monsoon systems, is a key area of research within environmental sciences. Monsoons, vital for billions of people, are complex atmospheric phenomena influenced by various global factors, including orbital changes and natural climate variability. Among monsoon systems, the Indian summer Monsoon (ISM) is of particular interest due to its significant impact on the South Asian climate, agriculture, and water resources. Despite extensive study, comprehending the ISM's historical variability and its future implications remains a challenge. Utilizing natural archives like speleothems, along with stable water isotopes from precipitation and advanced climate model simulations, this thesis aims to decipher the ISM's responses to natural forcings across key interglacial periods—the Last Interglacial and the Holocene.Our findings indicate that the ISM's strength is critically influenced by slight variations in orbital configurations, leading to significant shifts in monsoon patterns. Our research also highlights the dual influence of local geographical features and distant atmospheric conditions on the ISM's annual variability. Most notably, we observed discrepancies between δ18O values obtained from isotope-enabled climate models and those derived from speleothems. This insight indicates that the models need refinement to accurately mirror the complexities observed in the proxy records and that the uncertainty parameter in speleothem records needs to be improved.The alignment between proxy and model data is crucial for a more accurate reconstruction of past climates and for enhancing the predictive capabilities of future monsoon behavior under changing climatic conditions. By advancing our knowledge of the ISM's past, we are better equipped to anticipate its future. To achieve that, this thesis stresses the importance of bridging the gap between proxy data insights and climate model simulations. This would not only enrich our historical climate knowledge but also inform future climate projections, highlighting the indispensable role of interdisciplinary research in climate science challenges.
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| 3. |
- Bühler, Janica C., et al.
(författare)
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Investigating stable oxygen and carbon isotopic variability in speleothem records over the last millennium using multiple isotope-enabled climate models
- 2022
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Ingår i: Climate of the Past. - : Copernicus GmbH. - 1814-9324 .- 1814-9332. ; 18:7, s. 1625-1654
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Tidskriftsartikel (refereegranskat)abstract
- The incorporation of water isotopologues into the hydrology of general circulation models (GCMs) facilitates the comparison between modeled and measured proxy data in paleoclimate archives. However, the variability and drivers of measured and modeled water isotopologues, as well as the diversity of their representation in different models, are not well constrained. Improving our understanding of this variability in past and present climates will help to better constrain future climate change projections and decrease their range of uncertainty. Speleothems are a precisely datable terrestrial paleoclimate archives and provide well-preserved (semi-)continuous multivariate isotope time series in the lower latitudes and mid-latitudes and are therefore well suited to assess climate and isotope variability on decadal and longer timescales. However, the relationships of speleothem oxygen and carbon isotopes to climate variables are influenced by site-specific parameters, and their comparison to GCMs is not always straightforward.Here we compare speleothem oxygen and carbon isotopic signatures from the Speleothem Isotopes Synthesis and Analysis database version 2 (SISALv2) to the output of five different water-isotope-enabled GCMs (ECHAM5-wiso, GISS-E2-R, iCESM, iHadCM3, and isoGSM) over the last millennium (850–1850 CE). We systematically evaluate differences and commonalities between the standardized model simulation outputs. The goal is to distinguish climatic drivers of variability for modeled isotopes and compare them to those of measured isotopes.We find strong regional differences in the oxygen isotope signatures between models that can partly be attributed to differences in modeled surface temperature. At low latitudes, precipitation amount is the dominant driver for stable water isotope variability; however, at cave locations the agreement between modeled temperature variability is higher than for precipitation variability. While modeled isotopic signatures at cave locations exhibited extreme events coinciding with changes in volcanic and solar forcing, such fingerprints are not apparent in the speleothem isotopes. This may be attributed to the lower temporal resolution of speleothem records compared to the events that are to be detected. Using spectral analysis, we can show that all models underestimate decadal and longer variability compared to speleothems (albeit to varying extents).We found that no model excels in all analyzed comparisons, although some perform better than the others in either mean or variability. Therefore, we advise a multi-model approach whenever comparing proxy data to modeled data. Considering karst and cave internal processes, e.g., through isotope-enabled karst models, may alter the variability in speleothem isotopes and play an important role in determining the most appropriate model. By exploring new ways of analyzing the relationship between the oxygen and carbon isotopes, their variability, and co-variability across timescales, we provide methods that may serve as a baseline for future studies with different models using, e.g., different isotopes, different climate archives, or different time periods.
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