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The evolution and variation history of the Tsushima warm current during the late Quaternary was reconstructed based on the quantitative census data of planktonic foraminiferal fauna, together with oxygen and carbon isotope records of mixed layer dweller a ruber and thermocline dweller N. dutertrei in piston core CSH1 and core DGKS9603 collected separately from the Tsushima warm current and the Kuroshio dominated area. The result showed that the Tsushima warm current vanished in the lowstand period during 40-24 cal ka BP, while the Kuroshio still flowed across the Okinawa Trough, arousing strong upwelling in the northern Trough. Meanwhile, the influence of freshwater greatly increased in the northern Okinawa Trough, as the broad East China Sea continental shelf emerged. The freshwater reached its maximum during the last glacial maximum (LGM), when the upwelling obviously weakened for the lowest sea-level and the depression of the Kuroshio. The modern Tsushima warm current began its development since 16 cal ka BP, and the impact of the Kuroshio increased in the middle and northern Okinawa Trough synchronously during the deglaciation and gradually evolved as the main water source of the Tsushima current. The modern Tsushima current finally formed at about 8.5 cal ka BP, since then the circulation structure has been relatively stable. The water of the modern Tsushima current primarily came from the Kuroshio axis. A short-term wiggle of the current occurred at about 3 cal ka BP, probably for the influences from the enhancement of the winter monsoon and the depression of the Kuroshio. The cold water masses greatly strengthened during the wiggle.

Equimolecular amounts of amino acids (l-leucine and l-valine) and d-glucose were refluxed at 140 °C for 2 h in propylene glycol. The volatiles were isolated by simultaneous steam distillation and extraction. The extracts were separated in advance by column chromatography on silica gel with a benzene−ether gradient. The resulting fractions were analyzed by GC and GC-MS. Twenty-seven compounds, including 13 pyrazines, 6 dioxolanes, 2 aldehydes, 2 acids, and 2 pyridines, were identified. Dioxolanes, aldehydes, and pyrazines are the major volatiles, and the percentages of their total gas chromatographic peak areas are 41.13, 23.67, and 17.69 respectively. Formation pathways and sensory properties are described. Keywords: Volatile compounds; Maillard reaction; model reaction system