Two sediment cores recovered in the central part of Daihai Lake in north-central China were analysed at 2-to 4-cm intervals for total inorganic and organic carbon (TIC and TOC) concentrations. The TIC concentration is inferred to reflect temperatures over the lake region and an increase in the TIC concentration implies an increase in the temperature. TOC concentration is considered to reflect the precipitation in the lake basin and higher TOC concentrations denote more precipitations. Thus AMS 14C time series of the TIC and TOC records of Daihai Lake sediments uncovers a detailed history of changes in temperature and precipitation in north-central China during the last c. 12 000 yr. The Holocene, an epoch of postglacial warmth, started c. 11 500 cal. yr BP, and can be subdivided into three stages: the early (c. 11 500-8100 cal. yr BP), middle (c. 8100-3300 cal. yr BP) and the late Holocene (c. 3300-0 cal. yr BP). The climate was warm and dry during the early Holocene, warm and wet during the middle Holocene, and in the late Holocene became cooler and drier but displayed a relatively warmer and wetter interval between c. 1700 and 1300 cal. yr BP. The Holocene Climatic Optimum, defined as a postglacial episode of both megathermal and megahumid climate, might have occurred in north-central China between c. 8100 and 3300 cal. yr BP, and the climate during this period was variable and punctuated by cool and/or dry events. We infer that changes in the temperature were directly controlled by changes in summer solar radiation in the Northern Hemisphere resulting from progressive changes in the Earth's orbital parameters. Whereas an increase in the monsoonal precipitation could be closely related to an increase in the sea surface temperature of the low-latitude Pacific Ocean, an increase in the temperature and size of the Western Pacific Warm Pool and a westward shifted and strengthened Kuroshio Current in the western Pacific.

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Highlights d A three-dimensional architecture of the HNS with high resolution was reconstructed d Magnocellular neuroendocrine cells collaterally projected to extrahypothalamic areas d Activation of Magno-OXT neurons promoted social behavior and peripheral OXT release d Inhibition of Magno-OXT neurons elicited opposite effects

Astrocytes respond to and regulate neuronal activity, yet their role in mammalian behavior remains incompletely understood. Especially unclear is whether, and if so how, astrocyte activity regulates contextual fear memory, the dysregulation of which leads to pathological fear-related disorders. We generated GFAP-ChR2-EYFP rats to allow the specific activation of astrocytes in vivo by optogenetics. We found that after memory acquisition within a temporal window, astrocyte activation disrupted memory consolidation and persistently decreased contextual but not cued fear memory accompanied by reduced fear-related anxiety behavior. In vivo microdialysis experiments showed astrocyte photoactivation increased extracellular ATP and adenosine concentrations. Intracerebral blockade of adenosine A1 receptors (A1Rs) reversed the attenuation of fear memory. Furthermore, intracerebral or intraperitoneal injection of A1R agonist mimicked the effects of astrocyte activation. Therefore, our findings provide a deeper understanding of the astrocyte-mediated regulation of fear memory, and suggest a new and important therapeutic strategy against pathological fear-related disorders.