35 research outputs found

    High-temperature oxidation of nickel-based alloys and estimation of the adhesion strength of resulting oxide layers

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    The kinetics of isothermal oxidation (1100°C) of commercial nickel-based alloys with different content of sulfur (0.22–3.2 wt ppm) is studied. The adhesion strength in a metal/oxide system is estimated as a function of sulfur content and duration of high-temperature exposure. The scratch-test technique is proposed to quantitatively estimate the work of adhesion of resulting oxide films. It is found that the film microstructure is composed of an inner α-Al2O3 layer and an outer NiAl2O4 spinel layer, which are separated by discrete inclusions of TiO2. Residual stresses in the oxide film are experimentally determined by X-ray diffraction. spinel layer, which are separated by discrete inclusions of TiO2. Residual stresses in the oxide film are experimentally determined by X-ray diffractio

    Hormone therapy and fractures in postmenopausal women

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    Background:Fracture rates have been reported to be higher among older women living with HIV (WLWH) than HIV- women. Hormone therapy with estrogen can reduce vasomotor symptoms (VMS) associated with menopause and prevent fractures. As data are limited on the benefits of hormone therapy use in WLWH, we examined associations of hormone therapy, use and fractures.Methods:A prospective study of 1765 (1350 WLWH and 415 HIV-) postmenopausal Women's Interagency HIV Study (WIHS) participants was performed, including self-reported hormone therapy, use and fracture data from 2003 to 2017. Proportional hazard models determined predictors of new fractures at any site or at typical fragility fracture sites (hip, spine, wrist).Results:At the first postmenopausal visit, the median (IQR) age of WLWH was slightly younger than HIV- women [49.8 (46.4-53) vs. 50.7 (47.5-54), P = 0.0002] and a smaller proportion of WLWH reported presence of VMS (17% vs. 26%, P < 0.0001). A greater proportion of WLWH than HIV- women reported hormone therapy use (8% vs. 4%, P = 0.007) at the first postmenopausal visit. In multivariate analyses, white race and smoking were significant predictors of incident fracture at any site but hormone therapy (P = 0.69) and HIV status (P = 0.53) were not.Conclusion:Our study did not find evidence of benefit or harm with regards to fracture outcomes in postmenopausal WLWH receiving hormone therapy. Further research is needed to determine whether hormone therapy has benefits beyond treatment of VMS, such as prevention of adverse aging-associated outcomes

    Contributions of HIV, hepatitis C virus, and traditional vascular risk factors to peripheral artery disease in women

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    Objectives:HIV and hepatitis C virus (HCV) have been associated with cardiovascular disease (CVD), but it is unclear whether HIV and HCV are also associated with peripheral artery disease (PAD). We examined the association of HIV, HCV, and traditional CVD risk factors with PAD in the Women's Interagency HIV Study, a multicenter US cohort.Methods:In this cross-sectional study, ankle-brachial index was estimated using Doppler ultrasound and manual sphygmomanometer in 1899 participants aged more than 40 years with HIV/HCV coinfection, HCV or HIV monoinfection, or neither infection. Multivariable logistic regression was used to estimate the odds of PAD (ankle-brachial index ≤0.9) after controlling for demographic, behavioral, and CVD risk factors.Results:Over two-thirds were African-American, median age was 50 years, and PAD prevalence was 7.7% with little difference by infection status. After multivariable adjustment, neither HIV nor HCV infection was associated with greater odds of PAD. Factors associated with PAD included older age [adjusted odds ratio (aOR): 2.01 for age 61-70 vs. 40-50 years; 95% confidence interval (CI): 1.04, 3.87], Black race (aOR: 2.30; 95% CI: 1.15, 4.63), smoking (aOR: 1.27 per 10-pack-year increment; 95% CI: 1.09, 1.48), and higher SBP (aOR: 1.14 per 10 mmHg; 95% CI: 1.01, 1.28).Conclusion:The high PAD prevalence in this nationally representative cohort of women with or at risk for HIV is on par with general population studies in individuals a decade older than our study's median age. HIV and HCV infection are not associated with greater PAD risk relative to uninfected women with similar risk factors. Modifiable traditional CVD risk factors may be important early intervention targets in women with and at risk for HIV

    Toestand vis en visserij in de zoete Rijkswateren. Deel II: Methoden

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    Sinds 2013 worden al deze monitoringprogramma’s jaarlijks in één rapportage gebundeld. Dit rapport bevat de gebruikte methodieken van de verschillende vis-monitoringsprogramma’s in de zoete Rijkswatere

    Menopausal Hormone Therapy and Subclinical Cardiovascular Disease in Women With and Without Human Immunodeficiency Virus

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    Background: Estrogen-based hormone therapy (HT) may have beneficial cardiovascular effects when initiated in early menopause. This has not been examined in women with human immunodeficiency virus (HIV), who have heightened immune activation and cardiovascular risks. Methods: Among 609 postmenopausal women (1234 person-visits) in the Women's Interagency HIV Study, we examined the relationship of ever HT use (oral, patch, or vaginal) with subclinical atherosclerosis: carotid artery intima-media thickness (CIMT), distensibility, and plaque assessed via repeated B-mode ultrasound imaging (2004-2013). We also examined associations of HT with cross-sectional biomarkers of immune activation and D-dimer. Statistical models were adjusted for sociodemographic, behavioral, and cardiometabolic factors. Results: Women (mean age, 51 years; 80% HIV positive) who ever used HT at baseline were older, and more likely to be non-Hispanic White and report higher income, than never-users. Women who ever used HT had 43% lower prevalence of plaque (prevalence ratio, 0.57 [95% confidence interval {CI},. 40-.80]; P <. 01), 2.51 μm less progression of CIMT per year (95% CI, -4.60, to -.41; P =. 02), and marginally lower incidence of plaque over approximately 7 years (risk ratio, 0.38 [95% CI,. 14-1.03; P =. 06), compared with never-users, adjusting for covariates; ever HT use was not associated with distensibility. These findings were similar for women with and without HIV. Ever HT use was associated with lower serum D-dimer, but not with biomarkers of immune activation after covariate adjustment. Conclusions: HT may confer a subclinical cardiovascular benefit in women with HIV. These results begin to fill a knowledge gap in menopausal care for women with HIV, in whom uptake of HT is very low

    Genomic and Molecular Landscape of DNA Damage Repair Deficiency across The Cancer Genome Atlas

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    DNA damage repair (DDR) pathways modulate cancer risk, progression, and therapeutic response. We systematically analyzed somatic alterations to provide a comprehensive view of DDR deficiency across 33 cancer types. Mutations with accompanying loss of heterozygosity were observed in over 1/3 of DDR genes, including TP53 and BRCA1/2. Other prevalent alterations included epigenetic silencing of the direct repair genes EXO5, MGMT, and ALKBH3 in 3c20% of samples. Homologous recombination deficiency (HRD) was present at varying frequency in many cancer types, most notably ovarian cancer. However, in contrast to ovarian cancer, HRD was associated with worse outcomes in several other cancers. Protein structure-based analyses allowed us to predict functional consequences of rare, recurrent DDR mutations. A new machine-learning-based classifier developed from gene expression data allowed us to identify alterations that phenocopy deleterious TP53 mutations. These frequent DDR gene alterations in many human cancers have functional consequences that may determine cancer progression and guide therapy. Knijnenburg et al. present The Cancer Genome Atlas (TCGA) Pan-Cancer analysis of DNA damage repair (DDR) deficiency in cancer. They use integrative genomic and molecular analyses to identify frequent DDR alterations across 33 cancer types, correlate gene- and pathway-level alterations with genome-wide measures of genome instability and impaired function, and demonstrate the prognostic utility of DDR deficiency scores
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