[1] Volcanoes emit larger amounts of volcanic gas than can be dissolved in the volume of erupted magma during a variety of volcanic processes, including explosive and effusive eruption and noneruptive continuous degassing. Degassing of unerupted magma with a much larger volume than that of erupted magma caused such a large degassing; erupted magma represents only a small portion of the magma that drives volcanic activity. Evaluation of the magma-gas differentiation process causing the excess degassing is necessary to understand eruption processes, magma chamber evolution, and crustal growth by magma intrusion. Three mechanisms are proposed to explain various degassing modes, including eruption of bubbleaccumulated magma, degassing of a convecting magma column, and permeable gas transportation from a deep magma chamber. Examples of large degassing in excess of the erupted magma are common in subduction zone volcanism but are rare in rift-and hot spot -associated volcanism.Citation: Shinohara, H. (2008), Excess degassing from volcanoes and its role on eruptive and intrusive activity, Rev. Geophys., 46, RG4005,

Pax6 is a highly conserved transcription factor among vertebrates and is important in various developmental processes in the central nervous system (CNS), including patterning of the neural tube, migration of neurons, and formation of neural circuits. In this review, we focus on the role of Pax6 in embryonic and postnatal neurogenesis, namely, production of new neurons from neural stem/progenitor cells, because Pax6 is intensely expressed in these cells from the initial stage of CNS development and in neurogenic niches (the subgranular zone of the hippocampal dentate gyrus and the subventricular zone of the lateral ventricle) throughout life. Pax6 is a multifunctional player regulating proliferation and differentiation through the control of expression of different downstream molecules in a highly context-dependent manner.

It is generally accepted, but not experimentally proven, that a quantitative prediction of volcanic eruptions is possible from the evaluation of volcanic gas data. By discussing the results of two years of real-time observation of H 2 O, CO 2 , and SO 2 in volcanic gases from Mount Etna volcano, we unambiguously demonstrate that increasing CO 2 /SO 2 ratios can allow detection of the pre-eruptive degassing of rising magmas. Quantitative modeling by the use of a saturation model allows us to relate the pre-eruptive increases of the CO 2 /SO 2 ratio to the refi lling of Etna's shallow conduits with CO 2 -rich deep-reservoir magmas, leading to pressurization and triggering of eruption. The advent of real-time observations of H 2 O, CO 2 , and SO 2 , combined with well-constrained models of degassing, represents a step forward in eruption forecasting.

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