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Tropical cyclones (TCs) often affect the surface sediments of coastal areas, and impact the sediment imprint. Although the sediment magnetism is sensitive to coastal changes, the understanding of the coastal magnetic minerals' redistribution affected by TCs is far from adequate. Here, the magnetic and grain-size records from the seafloor sediments along the Leizhou Peninsula coast in South China before and after two violent TCs (Mangkhut and Barijat) occurred in September 2018 are present. The magnetic minerals mainly consist of magnetite, hematite, and goethite. For most sites, the content of hematite increased compared to magnetite and the magnetic minerals became coarser after the TCs subsided, while the amount of fine clay (<2 μm) decreased and the amount of coarse sand (500–2000 μm) increased. This is due to the preferential deposition of the lamellae hematite from the soils and the enhanced hydrodynamic transportation of suspended sediments. The mangrove forest resists the change to a certain degree, especially in the Leizhou Bay. The magnetic and grain-size properties are sensitive to the TC-induced deposits, and provide convincing tools to aid in detecting the paleo-TC activity in tropical coastal regions. • Tropical cyclones (TCs) led to more content of hematite in coastal sediments compared to magnetite. • After the TCs, magnetic particles in sediments became coarser. • The <2 μm content decreased, and the 500–2000 μm content increased after the TCs. • The mangrove forests resist the redistribution of magnetic particles to a certain degree when the TCs landing. [ABSTRACT FROM AUTHOR]

Background: Accumulative evidence suggests that low folate intake is associated with increased risk of breast cancer. Polymorphisms in genes involved in folate metabolism may influence DNA methylation, nucleotide synthesis, and thus individual susceptibility to cancer. Thymidylate synthase (TYMS) is a key enzyme that participates in folate metabolism and catalyzes the conversion of dUMP to dTMP in the process of DNA synthesis. Two potentially functional polymorphisms [a 28-bp tandem repeat in the TYMS 5'-untranslated enhanced region (TSER) and a 6-bp deletion/insertion in the TYMS 3'-untranslated region (TS 3'-UTR)] were suggested to be correlated with alteration of thymidylate synthase expression and associated with cancer risk. Methods: To test the hypothesis that polymorphisms of the TYMS gene are associated with risk of breast cancer, we genotyped these two polymorphisms in a case-control study of 432 incident cases with invasive breast cancer and 473 cancer-free controls in a Chinese population. Results: We found that the distribution of TS3'-UTR (1494del6) genotype frequencies were significantly different between the cases and controls (P = 0.026). Compared with the TS3'-UTR del6/del6 wild-type genotype, a significantly reduced risk was associated with the ins6/ins6 homozygous variant genotype (adjusted OR = 0.58, 95% CI = 0.35-0.97) but not the del6/ins6 genotype (OR = 1.09, 95% CI = 0.82-1.46). Furthermore, breast cancer risks associated with the TS3'-UTR del6/del6 genotype were more evident in older women, postmenopausal subjects, individuals with a younger age at first-live birth and individuals with an older age at menarche. However, there was no evidence for an association between the TSER polymorphism and breast cancer risks. Conclusion: These findings suggest that the TS3'-UTR del6 polymorphism may play a role in the etiology of breast cancer. Further larger population-based studies as well as functional evaluation of the variants are warranted to confirm our findings. [ABSTRACT FROM AUTHOR]