Publications by authors named "Guoqiang Chu"

The Holocene temperature conundrum, the discrepancy between proxy-based Holocene global cooling and simulated global annual warming trends, remains controversial. Meanwhile, reconstructions and simulations show inconsistent spatial patterns of terrestrial temperature changes. Here we report Holocene alkenone records to address spatial patterns over mid-latitude Eurasia.

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In our previous study, a polyphenol-utilization targeted quinoa product was developed solid-state fermentation with . In this study, we investigated the polyphenol-related novel functions of the fermented product further. Compared with unfermented quinoa, fermented quinoa alleviated the trapping effect of the macromolecules, especially in the colonic fermentation stage, resulting in enhanced polyphenol bioaccessibility.

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During the 7-9th century, the Tibetan Empire constituted a superpower between the Tang Empire and Abbasid Caliphate: one that played significant roles in geopolitics in Asia during the Early Medieval Period. The factors which led to the rise and rapid decline of this powerful Empire, the only united historical regime on the Tibetan Plateau (TP), remain unclear. Sub-annual scale precipitation and decadal-scale temperature records of the central TP are presented, indicating that the height of this Empire coincided with a two-century long interval of uncharacteristically warm and humid climate.

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Climate changes had major impacts on the vegetation of East Asia during the last deglaciation. However, the rate and pattern of vegetation succession in response to large-scale climatic events during this interval are controversial. Here, we present well-dated decadal-resolution pollen records from annually laminated Maar Lake Xiaolongwan during the last deglaciation.

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Bupivacaine (BUP), which is widely used in anesthesia, can cause neurotoxicity and neurological abnormalities. This work intended to study the function of long non-coding RNA (lncRNA) OIP5 antisense RNA 1 (OIP5-AS1) in BUP-triggered neurotoxicity. OIP5-AS1, microRNA (miR)-34b, and nuclear factor of activated T cells 5 (NFAT5) levels were examined via real-time quantitative PCR (RT-qPCR).

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The cause of seasonal hydrologic changes in tropical East Asia during interstadial/stadial oscillations of the last glaciation remains controversial. Here, we show seven seasonal drought events that occurred during the relatively warm interstadials by phytolith and pollen records. These events are significantly manifested as high percentages of bilobate phytoliths and are consistent with the large zonal sea-surface temperature (SST) gradient from the western to eastern tropical Pacific, suggesting that the reduction in seasonal precipitation could be interpreted by westward shifts of the western Pacific subtropical high triggered by changes of zonal SST gradient over the tropical Pacific and Hadley circulation in the Northern Hemisphere.

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In this study, surface sediments along the Zayandehrud River (14 samples), and two dated core sediments (46 samples) from small artificial urban lakes at the middle section of the Zayandehrud River in the Gavkhooni basin in the central arid regions of Iran were analyzed for residual levels of 20 organochlorine pesticide (OCP) compounds. Total OCP concentrations ranged from 0.1 to 50.

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Prehistoric human activities were likely influenced by cyclic monsoon climate changes in East Asia. Here we report a decadal-resolution Holocene pollen record from an annually-laminated Maar Lake in Northeast China, a proxy of monsoon climate, together with a compilation of 627 radiocarbon dates from archeological sites in Northeast China which is a proxy of human activity. The results reveal synchronous ~500-year quasi-periodic changes over the last 8000 years.

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The Great Khingan Mountain range, Northeast China, is located on the northern limit of modern East Asian Summer Monsoon (EASM) and thus highly sensitive to the extension of the EASM from glacial to interglacial modes. Here, we present a high-resolution pollen record covering the last glacial maximum and the early Holocene from a closed crater Lake Moon to reconstruct vegetation history during the glacial-interglacial transition and thus register the evolution of the EASM during the last deglaciation. The vegetation history has gone through distinct changes from subalpine meadow in the last glacial maximum to dry steppe dominated by Artemisia from 20.

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Phytoliths represent one of the few available altitudinal vegetation proxies for mountain ecosystems. This study analyzed 41 topsoil phytolith samples collected from five altitudinal zones in the southern Himalaya as far as, and beyond, the timberline, from tropical forest (up to 1,000 m a.s.

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Contamination by polycyclic aromatic hydrocarbons (PAHs) in the southwest Caspian Sea was assessed by examination of 45 sediment samples, collected from the coasts of the Guilan Province in 2012 and analyzed for 29 PAHs. The concentrations of PAHs were in the range of 232.1-1,014 ng g(-1) dry weight (mean 520±246.

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In this study, 75 samples of two (210)Pb-dated cores from the southwest of the Caspian Sea were analysed for 30 compounds of polycyclic aromatic hydrocarbons (PAHs). The TPAH29 flux of the last six centuries ranged from 16.3 to 177.

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In this study, 84 surface sediment samples, from 28 Iranian rivers, 45 surface sediment samples and 31 samples from one core in the southwest of the Caspian Sea were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs). The results showed high variability of perylene in coastal surface sediments (1.3-123.

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Here we presented a high-resolution 5350-year pollen record from a maar annually laminated lake in East Asia (EA). Pollen record reflected the dynamics of vertical vegetation zones and temperature change. Spectral analysis on pollen percentages/concentrations of Pinus and Quercus, and a temperature proxy, revealed ~500-year quasi-periodic cold-warm fluctuations during the past 5350 years.

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