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Floods out of all other water problems cause very large damages in China. Previous flood management plans mainly focused on a single river by controlling its water level and conveyance capacity, while research on mitigation solutions to flooding issues in river-lake systems is scarce. This study considers the Huai River - Lake Hongze system, which is one of the largest river-lake systems in China. Very large damages associated with small floods are frequently observed in this river-lake system, although a series of flood management measures have been implemented in the Huai River Basin since the middle of the last century. An unstructured-grid finite-volume numerical model was applied to simulate hydrodynamic processes in this system, which is characterized by discrepant spatial scales between these two types of water bodies. It is found that the lake affects the upstream river flooding, but lowering the lake level would have limited effects that would be rapidly impaired by the sharp meander bend connecting the river and the lake. The artificial cutoff of this intensively-embanked bend has great potential in reducing the river stage and flood damages, as the construction of a diversion channel would shorten the flow path and increase the hydraulic gradient. This study extends the current knowledge about the hydrodynamics of river-lake systems and is beneficial to flood mitigation strategies for similar systems. [ABSTRACT FROM AUTHOR]

Polycystic ovary syndrome (PCOS) is generally considered a multifactorial disease caused by interactions between multiple susceptible genes and environmental factors. Glutamate cysteine ligase (GCL) is the rate-limiting enzyme in glutathione biosynthesis. This study examined the relationship between single nucleotide polymorphisms (SNPs) in the GCL catalytic subunit (GCLC C-129 T) and the modifier subunit (GCLM C-588 T) and PCOS. The two SNPs were genotyped in 1017 PCOS patients and 793 control women. Clinical, metabolic, hormonal, and oxidative stress parameters were also assessed. The frequencies of the CT + TT genotypes (21.6% vs. 27.7%) and T allele (11.5% vs. 14.7%) of SNP GCLC C-129 T were significantly lower in hyperandrogenism (HA)-PCOS patients than in control women. Logistic regression analysis revealed that the relative hazard of HA-PCOS was lower in individuals with the -129 T allele (CT + TT genotypes) than in those with the CC genotype (OR = 0.723, 95% CI: 0.571-0.915, P = 0.007). When using the GCLC-CC/GCLM-CC combined genotype as the reference category, the GCLC-CT + TT/GCLM-CC combined genotype was a protective factor for PCOS with HA (OR = 0.743, 95% CI: 0.566-0.976, P = 0.033). HA-PCOS patients with the -129 T allele had lower waist circumference, waist-to-hip ratio, and body mass index (BMI) and lower fasting insulin concentration and homeostatic model assessment of insulin resistance after correcting for age and BMI (P < 0.05). The T allele of SNP GCLC C-129 T and its combination with the CC genotype of SNP GCLM C-588 T are associated with decreased risk of HA-PCOS in Chinese women., (© 2021. Society for Reproductive Investigation.)