Abstract-Blood pressure and prevalence of high blood pressure are greater for northern than southern Chinese. Reasons for these differences are unclear. Relationships of north-south blood pressure differences with multiple dietary factors were investigated in 839 Chinese participants, International Study on Macronutrients and Blood Pressure (INTERMAP), 561 northern, 278 southern, aged 40 to 59 years. Daily nutrient intakes were determined from four 24-hour dietary recalls and 2 timed 24-hour urine collections. Average systolic/diastolic pressure levels were 7.4/6.9 mm Hg higher for northern than southern participants. Southern participants had lower body mass index, sodium intake, sodium/potassium ratio, and higher intake of calcium, magnesium, phosphorus, and vitamins A and C. Considered singly, with control for age and gender, several dietary variables (eg, body mass index, urinary sodium/potassium ratio, urinary sodium, dietary phosphorus, and magnesium) reduced north-south blood pressure differences by Ն10%. Controlled for age and gender, nondietary variables had little effect on north-south blood pressure differences. With inclusion in regression models of multiple dietary variables (sodium, potassium, magnesium or phosphorus, body mass index), north-south blood pressure differences became much smaller (systolic Ϫ1.1, diastolic 1.6 mm Hg) and statistically nonsignificant. In conclusion, multiple dietary factors accounted importantly for north-south blood pressure differences. Efforts are needed to improve nutrition in China, especially in the north, as well as in other populations including those in the United States, for prevention and control of adverse blood pressure levels and major adult cardiovascular disease.

Arabidopsis thaliana EARLY FLOWERING 3 (ELF3) as a zeitnehmer (time taker) is responsible for generation of circadian rhythm and regulation of photoperiodic flowering. There are two orthologs (OsELF3-1 and OsELF3-2) of ELF3 in rice (Oryza sativa), but their roles have not yet been fully identified. Here, we performed a functional characterization of OsELF3-1 and revealed it plays a more predominant role than OsELF3-2 in rice heading. Our results suggest OsELF3-1 can affect rice circadian systems via positive regulation of OsLHY expression and negative regulation of OsPRR1, OsPRR37, OsPRR73 and OsPRR95 expression. In addition, OsELF3-1 is involved in blue light signaling by activating EARLY HEADING DATE 1 (Ehd1) expression to promote rice flowering under short-day (SD) conditions. Moreover, OsELF3-1 suppresses a flowering repressor GRAIN NUMBER, PLANT HEIGHT AND HEADING DATE 7 (Ghd7) to indirectly accelerate flowering under long-day (LD) conditions. Taken together, our results indicate OsELF3-1 is essential for circadian regulation and photoperiodic flowering in rice.