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The superconducting transport properties of the conducting LaAlO3/SrTiO3 interface have been investigated in perpendicular and parallel magnetic fields. A large anisotropy in the transport properties is measured and the two-dimensional nature of the superconducting gas is confirmed. Analyses of the resistance versus temperature and magnetic field, as well as of the correlation length as a function of the magnetic field close to the superconducting critical temperature (about 200 mK), yield an estimate of ∼10 nm for the superconducting layer thickness.

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T-type voltage-gated calcium channels are expressed in the dendrites of many neurons, although their functional interactions with postsynaptic receptors and contributions to synaptic signaling are not well understood. We combine electrophysiological and ultrafast two-photon calcium imaging to demonstrate that mGluR1 activation potentiates cerebellar Purkinje cell Ca v 3.1 T-type currents via a G-protein-and tyrosine-phosphatase-dependent pathway. Immunohistochemical and electron microscopic investigations on wild-type and Ca v 3.1 gene knock-out animals show that Ca v 3.1 T-type channels are preferentially expressed in Purkinje cell dendritic spines and colocalize with mGluR1s. We further demonstrate that parallel fiber stimulation induces fast subthreshold calcium signaling in dendritic spines and that the synaptic Ca v 3.1-mediated calcium transients are potentiated by mGluR1 selectively during bursts of excitatory parallel fiber inputs. Our data identify a new fast calcium signaling pathway in Purkinje cell dendritic spines triggered by short burst of parallel fiber inputs and mediated by T-type calcium channels and mGluR1s.

The influence of quantum effects on the critical properties of an n-component vector model for structural phase transitions is explored, It is shown for n = 1, 2, and 00 that these effects can suppress the occurrence of a phase transition for all dimensions d. This turns out to be of particular relevance for systems where the classical transition temperature almost vanishes (T, = 0 represents the displacive limit). We also discuss the critical properties at this limit for n = cc and show that the critical exponents change discontinously,

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