17 research outputs found

    Characterization of powder-precursor HVOF-sprayed Al₂O₃-YSZ/ZrO₂ coatings

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    Abstract Thermal spraying using liquid feedstock can produce coatings with very fine microstructures either by utilizing submicron particles in the form of a suspension or through in situ synthesis leading, for example, to improved tribological properties. The focus of this work was to obtain a bimodal microstructure by using simultaneous hybrid powder-precursor HVOF spraying, where nanoscale features from liquid feedstock could be combined with the robustness and efficiency of spraying with powder feedstock. The nanostructure was achieved from YSZ and ZrO₂ solution-precursors, and a conventional Al₂O₃ spray powder was responsible for the structural features in the micron scale. The microstructures of the coatings revealed some clusters of unmelted nanosized YSZ/ZrO₂ embedded in a lamellar matrix of Al₂O₃. The phase compositions consisted of Îł- and α-Al₂O₃ and cubic, tetragonal and monoclinic ZrO₂. Additionally, some alloying of the constituents was found. The mechanical strength of the coatings was not optimal due to the excessive amount of the nanostructured YSZ/ZrO₂ addition. An amount of 10 vol.% or 7 wt.% 8YSZ was estimated to result in a more desired mixing of constituents that would lead to an optimized coating architecture

    Impact of obesity on angiogenic and inflammatory markers in the Finnish Genetics of Pre-eclampsia Consortium (FINNPEC) cohort

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    Abstract Background: While several studies have demonstrated that obesity increases the risk of pre-eclampsia (PE), the mechanisms have yet to be elucidated. We assessed the association between maternal/paternal obesity and PE and hypothesized that maternal body mass index (BMI) would be associated with an adverse inflammatory and angiogenic profile. High-sensitivity C-reactive protein (hs-CRP) and following serum angiogenic markers were determined: soluble endoglin (sEng), soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF). Methods: Data on BMI were available from 1450 pregnant women with PE and 1065 without PE. Serum concentrations of hs-CRP and angiogenic markers were available from a subset at first and third trimesters. Results: Prepregnancy BMI was higher in the PE group than in controls (mean ± SD) 25.3 ± 5.2 vs. 24.1 ± 4,4, p < 0.001, adjusted for parity, mother’s age, and smoking status before pregnancy. Increased hs-CRP concentrations were observed in both PE and non-PE women similarly according to BMI category. In women with PE, a higher BMI was associated with lower sFlt-1 and sEng concentrations throughout the pregnancy (p = 0.004, p = 0.008, respectively). There were no differences in PlGF in PE women according to BMI. Conclusions: We confirmed increased pre-pregnancy BMI in women with PE. Enhanced inflammatory state was confirmed in all women with overweight/obesity. Partly paradoxically we observed that PE women with obesity had less disturbed levels of angiogenic markers than normal weight women with PE. This should be taken into account when angiogenic markers are used in PE prediction. Acknowledgements FINNPEC Members: Hannele Laivuori2,7,8,9 (2Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland, 7Institute for Molecular Medicine Finland (FIMM), Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland, 8Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland, 9Department of Obstetrics and Gynecology, Tampere University Hospital, Tampere, Finland), Seppo Heinonen2 (2Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland), Eero Kajantie10,11,12 (10Chronic Disease Prevention Unit, National Institute for Health and Welfare, Helsinki, Finland, 11Children’s Hospital, Helsinki University Hospital and University of Helsinki, Helsinki, Finland, 12PEDEGO Research Unit, MRC Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland), Juha Kere13,14,15 (13Department of Biosciences and Nutrition, and Science for Life Laboratory, Karolinska Institutet, Stockholm, Sweden, 14Molecular Neurology Research Program, University of Helsinki, Helsinki, Finland, 15FolkhĂ€lsan Institute of Genetics, Helsinki, Finland), Katja Kivinen16 (16Division of Cardiovascular Medicine, University of Cambridge, Cambridge, UK), Anneli Pouta13,17 (13Department of Biosciences and Nutrition, and Science for Life Laboratory, Karolinska Institutet, Stockholm, Sweden, 17Department of Government Services, National Institute for Health and Welfare, Helsinki, Finland

    Press hardening of zinc-coated boron steels:role of steel composition in the development of phase structures within coating and interface regions

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    Abstract Zn and ZnFe coated 22MnB5 and 34MnB5 steels were subjected to the direct press hardening process in order to investigate the influence of steel composition on the resulting phase structures. Microstructures were characterized using advanced methods of microscopy. In addition, X-ray diffraction, glow discharge optical emission spectroscopy and thermodynamic calculations with Thermo-CalcÂź were carried out to support the analysis. The results indicate that the steel composition has a clear effect on the phase development within coating and interface regions. Whereas the behavior of the 22MnB5 was comparable to earlier investigations, a clearly non-conventional behavior of the 34MnB5 was observed: the formation of martensitic micro constituents, designated here as αâ€Č-Fe(Zn), were identified after die-quenching. The regions of the αâ€Č-Fe(Zn) formed mainly in vicinity of steel/coating interface and were emerged into the steel by sharing martensitic morphology with the base steel. The thermodynamic calculations suggest that carbon is effective in stabilizing the Îł-Fe(Zn) phase, which enables the formation of the αâ€Č-Fe(Zn) in fast cooling. Therefore, the higher initial C content of the 34MnB5 may result in the kinetic stabilization of the Îł-Fe(Zn) as the inter-diffusion between Zn and Fe occurs during annealing. Simultaneously occurring carbon partitioning from α-Fe(Zn) to Îł-Fe(Zn) could explain a clearly increased C content of the coating/steel interface as well as higher Zn contents in the αâ€Č-Fe(Zn) phase compared to 22MnB5. Actually, the present study shows that the same phenomenon occurs also in 22MnB5 steels, but in a much smaller scale. In Zn and ZnFe coated 34MnB5, the thickness of the αâ€Č-Fe(Zn) layer was increased with longer annealing times and at higher temperatures. The morphology of the αâ€Č-Fe(Zn) layer resembled plate-like martensite and can be assumed to be brittle. Regarding this, the formation of αâ€Č-Fe(Zn) interface layer needs to be taken into account in press hardening of 34MnB5 steels

    Properties of HVOF-sprayed Stellite-6 coatings

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    Abstract Stellite-6 coatings were deposited onto AISI 304 stainless steel substrate by gas-fueled HVOF spraying, systematically varying the process parameter settings. By operating the HVOF torch with a fuel-rich mixture, dense coatings (&lt;1% porosity) are produced, containing up to ≈3 vol% oxide inclusions. A substantial amount of a Cr-rich f.c.c. phase is found, mainly produced by quenching of molten lamellae, and distinct from the equilibrium, Co-based f.c.c. solid solution retained in unmelted particles. These coatings exhibit pseudo-passive behavior and survive 5 cycles (100 h) of the Corrodkote test (ASTM B380-97) with no substrate corrosion. Coatings obtained from oxygen-rich mixtures, on the other hand, contain fewer oxide inclusions but also greater porosity, and do not protect the substrate against corrosion. The wear behavior of the coatings is less influenced by deposition conditions. In ball-on-disk dry sliding tests, all coatings exhibit wear rates of 2-3 × 10⁻⁔ mmÂł/(N·m), higher than those reported for bulk or clad Stellite, because of interlamellar delamination. Strain-induced, “martensitic” phase transformation from the f.c.c. structure to a h.c.p. one is observed over a 1-2â€ŻÎŒm depth below the contact surface. Additional tribo-oxidation is onset when frictional heat dissipation has heated the wear debris enough to trigger its reaction with the environment. Correspondingly, a transition to a regime of higher friction occurs (from ≈0.6 to ≈0.8). At 400 °C, lamellar delamination is suppressed but wear rates rise to 5-8 × 10⁻⁔ mmÂł/(N·m) because of abrasive and adhesive wear. At 800 °C, a dense “glaze” tribofilm is formed by sintered debris particles, firmly bonded to a thermally grown oxide scale on the underlying metal surface. The “glaze” protects the coating, lowering the wear rate to ≈1 × 10⁻⁔ mmÂł/(N·m) and the friction coefficient to &lt;0.45. Under high-stress particle abrasion conditions, wear rates of ≈1 × 10⁻³ mmÂł/(N·m) are found

    Analysis of composition, morphology, and biosynthesis of cuticular wax in wild type bilberry (Vaccinium myrtillus L.) and its glossy mutant

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    Abstract In this study, cuticular wax load, its chemical composition, and biosynthesis, was studied during development of wild type (WT) bilberry fruit and its natural glossy type (GT) mutant. GT fruit cuticular wax load was comparable with WT fruits. In both, the proportion of triterpenoids decreased during fruit development concomitant with increasing proportions of total aliphatic compounds. In GT fruit, a higher proportion of triterpenoids in cuticular wax was accompanied by a lower proportion of fatty acids and ketones compared to WT fruit as well as lower density of crystalloid structures on berry surfaces. Our results suggest that the glossy phenotype could be caused by the absence of rod-like structures in GT fruit associated with reduction in proportions of ketones and fatty acids in the cuticular wax. Especially CER26-like, FAR2, CER3-like, LTP, MIXTA, and BAS genes showed fruit skin preferential expression patterns indicating their role in cuticular wax biosynthesis and secretion

    Persistently high levels of maternal antenatal inflammation are associated with and mediate the effect of prenatal environmental adversities on neurodevelopmental delay in the offspring

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    Abstract Background: Prenatal exposure to environmental adversities, including maternal overweight/obesity, diabetes/hypertensive disorders, or mood/anxiety disorders, increases the risk for adverse neurodevelopmental outcomes in children. However, the underlying biological mechanisms remain elusive. We tested whether maternal antenatal inflammation was associated with the number of neurodevelopmental delay areas in children and whether it mediated the association between exposure to any prenatal environmental adversity and child neurodevelopmental delay. Methods: Mother-child dyads (N = 418) from the PREDO (Prediction and Prevention of Preeclampsia and Intrauterine Growth Restriction) study were followed up to 10.8 years. We analyzed maternal plasma high-sensitivity C-reactive protein and glycoprotein acetyls at 3 consecutive antenatal time points, measured maternal body mass index in early pregnancy, extracted data on diabetes/hypertensive disorders in pregnancy from medical records, and extracted data on mood/anxiety disorders until childbirth from the Care Register for Health Care. To estimate the number of neurodevelopmental delay areas in children across cognitive, motor, and social functioning, we pooled data from the Care Register for Health Care on psychological development disorders with mother-reported Ages and Stages Questionnaire data on developmental milestones. Results: Higher levels of maternal high-sensitivity C-reactive protein and glycoprotein acetyls at and across all 3 antenatal time points were associated with 1.30- to 2.36-fold (p values &lt; 0.02) increased relative risk for higher number of areas of child neurodevelopmental delay. Higher maternal inflammation across the 3 time points also mediated the effect of any prenatal environmental adversity on child neurodevelopmental delay. Conclusions: Higher levels of maternal inflammation, especially when persisting throughout pregnancy, increase a child’s risk of neurodevelopmental delay and mediate the effect of prenatal environmental adversity on child neurodevelopmental delay

    Compositional and morphological analyses of wax in northern wild berry species

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    Abstract Aerial surfaces of plants are covered by a waxy cuticle protecting plants from excessive water loss and UV light. In the present study, composition and morphology of cuticular waxes of northern wild berry species bilberry (Vaccinium myrtillus L.), lingonberry (V. vitis-idaea L.), bog bilberry (V. uliginosum L.) and crowberry (Empetrum nigrum L.) were investigated. Scanning electron microscopy (SEM) revealed differences in epicuticular wax morphology, and gas chromatography–mass spectrometry (GC–MS) analysis confirmed variation in chemical composition of cuticular waxes between the berry species. The dominant compounds in bilberry and lingonberry cuticular waxes were triterpenoids, while fatty acids and alkanes were the dominant ones in bog bilberry and crowberry, respectively. Wax extracted by supercritical fluid extraction (SFE) from industrial press cakes of bilberry and lingonberry contained linoleic acid and γ-linolenic acid as the dominant compounds. Furthermore, in vitro sun protection factor (SPF) of berry waxes depicted good UV-B absorbing capacities

    Maternal depression and inflammation during pregnancy

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    Abstract Background: Maternal depression during pregnancy increases the risk for adverse developmental outcomes in children. However, the underpinning biological mechanisms remain unknown. We tested whether depression was associated with levels of and change in the inflammatory state during pregnancy, if early pregnancy overweight/obesity or diabetes/hypertensive pregnancy disorders accounted for/mediated these effects, and if depression added to the inflammation that typically accompanies these conditions. Methods: We analyzed plasma high-sensitivity C-reactive protein (hsCRP) and glycoprotein acetyls at three consecutive stages during pregnancy, derived history of depression diagnoses before pregnancy from Care Register for Healthcare (HILMO) (N = 375) and self-reports (N = 347) and depressive symptoms during pregnancy using the Center for Epidemiological Studies Depression Scale completed concurrently to blood samplings (N = 295). Data on early pregnancy body mass index (BMI) and diabetes/hypertensive pregnancy disorders came from medical records. Results: Higher overall hsCRP levels, but not change, during pregnancy were predicted by history of depression diagnosis before pregnancy [HILMO: mean difference (MD) = 0.69 standard deviation (s.d.) units; 95% confidence interval (CI) 0.26–1.11, self-report: MD = 0.56 s.d.; 95% CI 0.17–0.94] and higher depressive symptoms during pregnancy (0.06 s.d. per s.d. increase; 95% CI 0.00–0.13). History of depression diagnosis before pregnancy also predicted higher overall glycoprotein acetyls (HILMO: MD = 0.52 s.d.; 95% CI 0.12–0.93). These associations were not explained by diabetes/hypertensive disorders, but were accounted for and mediated by early pregnancy BMI. Furthermore, in obese women, overall hsCRP levels increased as depressive symptoms during pregnancy increased (p = 0.006 for interaction). Conclusions: Depression is associated with a proinflammatory state during pregnancy. These associations are mediated by early pregnancy BMI, and depressive symptoms during pregnancy aggravate the inflammation related to obesity

    Maternal early pregnancy obesity and depressive symptoms during and after pregnancy

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    Abstract Background: Previous studies have linked maternal obesity with depressive symptoms during and after pregnancy. It remains unknown whether obesity associates with consistently elevated depressive symptoms throughout pregnancy, predicts symptoms postpartum when accounting for antenatal symptoms, and if co-morbid hypertensive and diabetic disorders add to these associations. We addressed these questions in a sample of Finnish women whom we followed during and after pregnancy. Methods: Early pregnancy body mass index, derived from the Finnish Medical Birth Register and hospital records in 3234 PREDO study participants, was categorized into underweight (&lt;18.5 kg/mÂČ), normal weight (18.5–24.99 kg/mÂČ), overweight (25–29.99 kg/mÂČ), and obese (â©Ÿ30 kg/mÂČ) groups. The women completed the Center for Epidemiological Studies Depression Scale biweekly during pregnancy, and at 2.4 (S.D. = 1.2) and/or 28.2 (S.D. = 4.2) weeks after pregnancy. Results: In comparison to normal weight women, overweight, and obese women reported higher levels of depressive symptoms and had higher odds of clinically significant depressive symptoms during (23% and 43%, respectively) and after pregnancy (22% and 36%, respectively). Underweight women had 68% higher odds of clinically significant depressive symptoms after pregnancy. Overweight and obesity also predicted higher depressive symptoms after pregnancy in women not reporting clinically relevant symptomatology during pregnancy. Hypertensive and diabetic disorders did not explain or add to these associations. Conclusions: Maternal early pregnancy overweight and obesity and depressive symptoms during and after pregnancy are associated. Mental health promotion should be included as an integral part of lifestyle interventions in early pregnancy obesity and extended to benefit also overweight and underweight women

    Associations of antenatal glucocorticoid exposure with mental health in children

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    Abstract Background: Synthetic glucocorticoids, to enhance fetal maturation, are a standard treatment when preterm birth before 34 gestational weeks is imminent. While morbidity- and mortality-related benefits may outweigh potential neurodevelopmental harms in children born preterm (&lt;37 gestational weeks), this may not hold true when pregnancy continues to term (â©Ÿ37 gestational weeks). We studied the association of antenatal betamethasone exposure on child mental health in preterm and term children. Methods: We included 4708 women and their children, born 2006–2010, from the Prediction and Prevention of Pre-eclampsia and Intrauterine Growth Restriction Study with information on both antenatal betamethasone treatment and child mental and behavioral disorders from the Finnish Hospital Discharge Register from the child’s birth to 31 December 2016. Additional follow-up data on mother-reported psychiatric problems and developmental milestones were available for 2640 children at 3.5 (s.d. = 0.07) years-of-age. Results: Of the children, 187 were born preterm (61 betamethasone-exposed) and 4521 at term (56 betamethasone-exposed). The prevalence of any mental and behavioral, psychological development, emotional and behavioral, and comorbid disorders was higher in the betamethasone-exposed, compared to non-exposed children [odds ratio 2.76 (95% confidence interval 1.76–4.32), 3.61 (2.19–5.95), 3.29 (1.86–5.82), and 6.04 (3.25–11.27), respectively]. Levels of psychiatric problems and prevalence of failure to meet the age-appropriate development in personal-social skills were also higher in mother-reports of betamethasone-exposed children. These associations did not vary significantly between preterm and term children. Conclusions: Antenatal betamethasone exposure may be associated with mental health problems in children born preterm and in those who end up being born at term
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