Associations between lifestyle factors and levels of per- and polyfluoroalkyl substances (PFASs), phthalates and parabens in follicular fluid in women undergoing fertility treatment

Background: Concerns have been raised whether exposure to endocrine-disrupting chemicals (EDCs) can alter reproductive functions and play a role in the aetiology of infertility in women. With increasing evidence of adverse effects, information on factors associated with exposure is necessary to form firm recommendations aiming at reducing exposure.Objective: Our aim was to identify associations between lifestyle factors including the home environment, use of personal care products (PCP), and dietary habits and concentrations of EDCs in ovarian follicular fluid.Methods: April-June 2016, 185 women undergoing ovum pick-up for in vitro fertilisation in Sweden were recruited. Correlation analyses were performed between self-reported lifestyle factors and concentration of EDCs analysed in follicular fluid. Habits related to cleaning, PCPs, and diet were assessed together with concentration of six per- and polyfluoroalkyl substances (PFASs) [PFHxS, PFOA, PFOS, PFNA, PFDA and PFUnDA], methyl paraben and eight phthalate metabolites [MECPP, MEHPP, MEOHP, MEHP, cxMinCH, cxMiNP, ohMiNP, MEP, MOHiBP]. Spearman's partial correlations were adjusted for age, parity and BMI.Results: Significant associations were discovered between multiple lifestyle factors and concentrations of EDCs in ovarian follicular fluid. After correcting p values for multiple testing, frequent use of perfume was associated with MEP (correlation rho = 0.41 (confidence interval 0.21-0.47), p < 0.001); hens' egg consumption was positively associated with PFOS (rho = 0.30 (0.15-0.43), p = 0.007) and PFUnDA (rho = 0.27 (0.12-0.40), p = 0.036). White fish consumption was positively associated with PFUnDA (rho = 0.34 (0.20-0.47), p < 0.001) and PFDA (rho = 0.27 (0.13-0.41), p = 0.028). More correlations were discovered when considering the raw uncorrected p values. Altogether, our results suggest that multiple lifestyle variables affect chemical contamination of follicular fluid.Impact statement: This study shows how lifestyle factors correlate with the level of contamination in the ovary by both persistent and semi-persistent chemicals in women of reproductive age. Subsequently, these data can be used to form recommendations regarding lifestyle to mitigate possible negative health outcomes and fertility problems associated with chemical exposure, and to inform chemical policy decision making. Our study can also help form the basis for the design of larger observational and intervention studies to examine possible effects of lifestyle changes on exposure levels, and to unravel the complex interactions between biological factors, lifestyle and chemical exposures in more detail

Follicular fluid and blood levels of persistent organic pollutants and reproductive outcomes among women undergoing assisted reproductive technologies

Persistent organic pollutants (POPs) are industrial chemicals resistant to degradation and have been shown to have adverse effects on reproductive health in wildlife and humans. Although regulations have reduced their levels, they are still ubiquitously present and pose a global concern. Here, we studied a cohort of 185 women aged 21-43 years with a median of 2 years of infertility who were seeking assisted reproductive technology (ART) treatment at the Carl von Linne Clinic in Uppsala, Sweden. We analyzed the levels of 9 organochlorine pesticides (OCPs), 10 polychlorinated biphenyls (PCBs), 3 polybrominated diphenyl ethers (PBDEs), and 8 perfluoroalkyl substances (PFASs) in the blood and follicular fluid (FF) samples collected during ovum pick-up. Impact of age on chemical transfer from blood to FF was analyzed. Associations of chemicals, both individually and as a mixture, to 10 ART endpoints were investigated using linear, logistic, and weighted quantile sum regression, adjusted for age, body mass index, parity, fatty fish intake and cause of infertility. Out of the 30 chemicals, 20 were detected in more than half of the blood samples and 15 in FF. Chemical transfer from blood to FF increased with age. Chemical groups in blood crossed the blood-follicle barrier at different rates: OCPs > PCBs > PFASs. Hexachlorobenzene, an OCP, was associated with lower anti-Miillerian hormone, clinical pregnancy, and live birth. PCBs and PFASs were associated with higher antral follicle count and ovarian response as measured by ovarian sensitivity index, but also with lower embryo quality. As a mixture, similar findings were seen for the sum of PCBs and PFASs. Our results suggest that age plays a role in the chemical transfer from blood to FF and that exposure to POPs significantly associates with ART outcomes. We strongly encourage further studies to elucidate the underlying mechanisms of reproductive effects of POPs in humans

Har du läst något under sommarlovet? Ingenting, har haft semester! : En kvalitativ och kvantitativ studie inriktad på läsmotivationen i årskurs 3

Det här är en kvalitativ och kvantitativ studie med syfte att undersöka läsmotivationen under sommarlovet hos elever i årskurs 3 samt även undersöka om det är några skillnader beroende på vilket kön eleven har. Studien undersöker detta med hjälp av enkäter 74 elevers läsning under sommarlovet och deras allmänna inställning till läsning. Av dessa 74 elever intervjuades 15 elever om deras läsvanor och vad som händer när de läser. Enkäterna visade att fler flickorna har en bättre inställning till läsning jämfört med pojkarnas inställning. Det visade sig även att elevernas val av genrer varierade mellan de olika könen. Utifrån intervjuerna framkom det att fler av flickorna som var intresserade av böcker och att nästan alla av flickorna hade någon vuxen som läste för dem jämfört med pojkarna där hälften svarade att någon förälder kunde läsa för dem ibland. Det resultat som framkommit har analyserats genom tidigare forskning men även utifrån ett sociokulturellt perspektiv eftersom det finns åsikter att eleverna lär sig genom samspel med andra och genom att använda sig av språkliga redskap för att lära sig.Godkänt datum 2019-06-17</p

Fem lärares åsikter kring arbetet med utomhusmatematik : En kvalitativ studie som undersöker möjligheter och begränsningar med utomhusmatematik.

Det här är en kvalitativ studie som undersöker lärares upplevelser kring arbetet med utomhusmatematikens möjligheter och begränsningar. Studien undersöker även vilka områden inom matematik som arbetas mest med utomhus. Studiens syfte är att ge kunskap om de begränsningar och möjligheter som metoden utomhusmatematik kan upplevas från lärare. Studien syftar även till att ge kunskap om utomhusmatematik och hjälpa lärare med att få information om metoden. Studien undersöker detta med hjälp av fem lärare från en skola. Det som framkom av intervjuerna var att det fanns många möjligheter och få begränsningar med utomhusmatematik. De möjligheter som nämndes av lärarna var bland annat att om matematiken användes både utomhus och inomhus så kunde fler elever förstå matematikinnehållet. En annan möjlighet var att eleverna får en mer lustfylld matematiklektion utomhus. De begränsningar som nämndes av lärarna var bland annat att det krävs mer planering och tydligare ledarskap för användandet av utomhusmatemati

Pipeline Fracture due to Compression-Tension Loading Caused by Foreign Object Impact

In areas frequented by fishing vessels, trawl equipment or anchors may interfere with pipelines and cause damage through impact, potential hooking, and ensuing release of the pipeline. This load sequence of denting followed by global bending and springback results in a complex stress and strain history. Experiments have shown that fracture in an impacted pipe typically arises along the bottom of the dent, where the material suffers high compressive strains in the impact and hooking phase, and a rapid change to tension during the rebound phase. High compressive strains may reduce the strain to failure significantly for a succeeding tensile phase. A common trait of ductile damage models is to account for damage through nucleation, growth and coalescence of voids, which traditionally is thought to occur during tension. In this study, an uncoupled phenomenological Cockcroft-Latham-type fracture model accounting for anisotropic damage is used. The fracture model is implemented in the explicit finite element programme IMPETUS Afea Solver, and calibrated using material tests. Simulations show that the proposed fracture model is able to account for the observed behaviour.publishedVersionCopyright © 2018 by ASM

Pipeline Fracture due to Compression-Tension Loading Caused by Foreign Object Impact

In areas frequented by fishing vessels, trawl equipment or anchors may interfere with pipelines and cause damage through impact, potential hooking, and ensuing release of the pipeline. This load sequence of denting followed by global bending and springback results in a complex stress and strain history. Experiments have shown that fracture in an impacted pipe typically arises along the bottom of the dent, where the material suffers high compressive strains in the impact and hooking phase, and a rapid change to tension during the rebound phase. High compressive strains may reduce the strain to failure significantly for a succeeding tensile phase. A common trait of ductile damage models is to account for damage through nucleation, growth and coalescence of voids, which traditionally is thought to occur during tension. In this study, an uncoupled phenomenological Cockcroft-Latham-type fracture model accounting for anisotropic damage is used. The fracture model is implemented in the explicit finite element programme IMPETUS Afea Solver, and calibrated using material tests. Simulations show that the proposed fracture model is able to account for the observed behaviour

Discrete modeling of low-velocity penetration in sand

In this paper, a discrete particle method was evaluated and used in numerical simulations of low-velocity penetration in sand. Hemispherical, blunt, and ogival-nosed impactors were tested at striking velocities below 5 m/s. The tests were conducted in a dropped-object-rig where the resisting force from the sand was measured continuously during the experiments. This provided a basis for comparison for the simulations. The shapes of the force-penetration depth curves were different for the various impactors, but the ultimate penetration depths were similar in all tests that were done with the same impact velocity. Three-dimensional discrete particle simulations were generally capable of describing the behavior of the sand. However, the peak resisting force was underestimated, which led to a slight overestimation of the ultimate penetration depth. This discrete particle method has previously been evaluated at high impact velocities. The results presented in this study supplement past results and show that the method can also be used to describe the overall response of sand subjected to low-velocity penetration