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The effect of iron-containing substances with different forms on the properties of carbon-black filled natural rubber compound is discussed. The ionic iron substances (Fe[Cl.sub.2], Fe[Cl.sub.3], Fe[(SA).sub.3]) have a detrimental effect on the rubber. Based on the oxidation induction temperature values, the relative deteriorating effects of ionic iron substances on the rubber are in the order: Fe[(SA).sub.3] > Fe[Cl.sub.3] [approximately equal to] Fe[Cl.sub.2]. Not only are the metal ions ([Fe.sup.2+], [Fe.sup.3+]) with adjacent stable oxidation states catalytically active in degrading rubber, but also the counterions have an influence on the effect of oxidation, particularly the stearic anion. Ionic iron materials can decrease the molecular weight, especially for the case of Fe[(SA).sub.3] as measured by gel permeation chromatography. Due to the degrading effect on the rubber molecules, Fe[(SA).sub.3] brings about a torque decrease in moving die rheometer and evident decrease of the Mooney viscosity at 100[degrees]C, which is different from the effects of [Fe.sub.2][O.sub.3] and 304L-Fe. The insoluble iron substances behave more like hard fillers. Additionally, Fe[(SA).sub.3] remarkably alters the bound rubber content and the tensile properties after aging via two different process (scission and crosslinking). Overall, this work has a thorough comparison of effect of iron-containing materials on rubber aging and provides useful inspiration to protect the rubber from deterioration by foreign reagents and regulating the rubber stability and degradation rate via introducing degradative metal ions. KEYWORDS aging, GPC, ionic iron substances, natural rubber, OIT, 1 | INTRODUCTION Investigation of mechanism on rubber autoxidation (degradation) is important in maintaining the lifetime/stability of rubber materials and developing the easy-degradable polymer material. Rubber degradation involves chain initiation, [...]

Objective. Endometriosis, which is a common disease affecting approximately 10% of women of reproductive age, usually causes dysmenorrhea and infertility, thus seriously harming the patients' physical and mental health. However, there is a mean delay of 6.7 years between the onset of the symptoms and the surgical diagnosis of endometriosis. There is an increasing amount of evidence that suggests that epigenetic aberrations, including deoxyribonucleic acid (DNA) methylation, play a definite role in the pathogenesis of endometriosis. This study aimed to explore the noninvasive or minimally invasive biomarkers of this disease. Materials and Methods. Six patients with surgically confirmed ovarian endometriosis and six patients who received IUD implantation for contraception without endometriosis were recruited in the East Hospital of Tongji University in 2018. The genome methylation profiling of the eutopic and ectopic endometrium of ovarian endometriosis patients and normal endometrial specimens from healthy women was determined using a methylation microarray test. The test screened methylation-differentiated 5′–C–phosphate–G–3′ (CpG) sites and then located the target genes affected by these sites following sequence alignment. Then, an additional 22 patients and 26 healthy controls were enrolled to further verify the difference in the selected genes between endometriosis patients and healthy women. The differential DNA methylation of the selected genes was validated via direct bisulfite sequencing and analysis of their messenger ribonucleic acid (mRNA) levels using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Results. Fifteen differentially methylated CpG sites were found among the patients and healthy women, and five CpG sites were mapped to the introns of the human leukocyte antigen-C (HLA-C) gene; these were highly polymorphic between different HLA-C alleles and were HLA-C ∗ 07 specific. The results indicated that the HLA-C ∗ 07 carrier patients exhibited significantly higher DNA methylation levels at the intron VII of HLA-C compared to the HLA-C ∗ 07 carrier healthy controls. High HLA-C ∗ 07 mRNA levels were also observed using qRT-PCR with HLA-C ∗ 07-specific primers, which indicated that the hypermethylation of CpG in intron VII might suppress a silencer that regulates HLA-C ∗ 07 expressions. Conclusion. Deoxyribonucleic acid hypermethylation in the intron VII of the HLA-C ∗ 07 gene appears to regulate the expression of HLA-C ∗ 07. The aberrant DNA methylation in this region was positively correlated with the occurrence of endometriosis. [ABSTRACT FROM AUTHOR]

Covalent grafting and electrostatic-driven assembly have been two strategies in constructing well-defined polyoxometalate (POM) assemblies to produce specific morphologies and desirable properties. The modification of anionic counter-ions of amphiphilic compounds in POM-surfactant hybrid systems is still unexploited. Herein, we report the co-assembly of a synthetic double-tailed magnetic surfactant (MagSurf), (C 18 ) 2 C 2 N + [FeCl 4 ] - , and POM, {Mo 72 Fe 30 }. The magnetic aggregate (POM/MagSurf) results from the building up hierarchical structures at a time-dependent interface. In this construct, both the MagSurfs and {Mo 72 Fe 30 } POMs contribute to and mutually strengthen the magnetization of the designed magnetic assembles. Interestingly, the POM/MagSurf aggregates are compatible with aqueous mixtures and successfully employed to serve as magnetic transporting vehicles to anchor and deliver a protein molecule, myoglobin (Mb). Upon applying a magnetic field (0.3 T), the magnetic aggregates induced a directional migration and enrichment of the Mb protein (71-90%). During this process, the protein/POM/MagSurf complexes exhibited strong interactions facilitating stable anchoring and efficient enrichment of the Mb., (Copyright © 2018 Elsevier Inc. All rights reserved.)