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Seagrasses are important ecosystems that inhabit shallow coastal waters. They offer valuable ecosystem services (e.g., nutrient cycling, water quality control, and carbon sequestration) and provide favorable habitat for species (McGlathery et al., 2007; Nagelkerken et al., 2000; Oreska et al., 2017). They are also commonly referred to as natural eco-engineers that can effectively modify physical environments and stabilize the seabed (Jones et al., 1994). Previous studies on seagrass interactions with physical environments have shown that seagrasses can significantly modify the mean flow and turbulent structure (Fonseca & Fisher, 1986;

BackgroundThyroid nodules (TNs) are common thyroid lesions in older population. Few studies have focused on the prevalence of TNs and their relationship to lifestyle characteristics and dietary habits in centenarians. The current study aimed at determining the prevalence of TNs in Chinese centenarians by using high-resolution ultrasound (US) equipment and at investigating its relationship to lifestyle characteristics and dietary habits.Participants and methodsThe current study was part of the China Hainan Centenarian Cohort Study that was conducted in Hainan, an iodine-sufficient region in People’s Republic of China. A total of 874 permanent residents aged ≥100 years (mean age =102.8±2.8 years) without any missing data were included in the analysis.ResultsAmong the participants, 649 of them were detected at least one TN under the US examinations. The overall prevalence rate of TNs was 74.3%. The prevalence of TNs was higher in participants who were women, had hypertension, had diabetes, and were underweight compared with their counterparts. Multivariate logistic regression analyses showed that being female, hypertensive, and diabetic; betel quid consumption; and red meat consumption were independent risk factors, while being underweight and nut consumption were independent protective factors for TNs.ConclusionOur findings indicate that the presence of TNs was highly prevalent in Chinese centenarians, particularly in women. In addition to gender, having hypertension, having diabetes, and being underweight, the presence of TNs was independently associated with betel quid, red meat, and nut consumption. Further prospective studies are warranted to verify these associations in populations from different age strata, races, cultures, and iodine supplementation.

High electrical conductivity in the shallow mantle has long been recognized by electromagnetic depth soundings, but the origin remains debated. Various candidates, of which the two most popular are water enrichment in olivine (the dominant mineral in the upper mantle) and partial melt, have been proposed to explain the electrical anomalies. These models nearly exclusively assume a very low conductivity for dry or water‐poor olivine. Here, we show by experimental work that, under well‐controlled conditions of pressure, temperature, oxygen fugacity (fO2), and water inventory, the conductivity of olivine is in fact insensitive to water content at mantle temperature (e.g., >1,000°C), although the enhancement is substantial at relatively low temperature. In particular, the conductivity of olivine at temperature beyond ∼1,000°C is strikingly high, about 0.01–0.1 S/m, at the oxidizing conditions of the shallow mantle. The high conductivity is comparable to the geophysically measured high conductivity in many conductive regions of the shallow mantle. The results provide a new framework for understanding the electrical anomalies and electrical structure of the shallow mantle.