University of Coimbra

About: University of Coimbra is a education organization based out in Coimbra, Portugal. It is known for research contribution in the topics: Population & Mitochondrion. The organization has 14318 authors who have published 43067 publications receiving 994733 citations. The organization is also known as: UC & Universidade dos Estudos Gerais.

Early synaptic deficits in the APP/PS1 mouse model of Alzheimer's disease involve neuronal adenosine A2A receptors.

Abstract: Synaptic plasticity in the autoassociative network of recurrent connections among hippocampal CA3 pyramidal cells is thought to enable the storage of episodic memory. Impaired episodic memory is an early manifestation of cognitive deficits in Alzheimer's disease (AD). In the APP/PS1 mouse model of AD amyloidosis, we show that associative long-term synaptic potentiation (LTP) is abolished in CA3 pyramidal cells at an early stage. This is caused by activation of upregulated neuronal adenosine A2A receptors (A2AR) rather than by dysregulation of NMDAR signalling or altered dendritic spine morphology. Neutralization of A2AR by acute pharmacological inhibition, or downregulation driven by shRNA interference in a single postsynaptic neuron restore associative CA3 LTP. Accordingly, treatment with A2AR antagonists reverts one-trial memory deficits. These results provide mechanistic support to encourage testing the therapeutic efficacy of A2AR antagonists in early AD patients.

Nonlocal homogenization model for a periodic array of epsilon-negative rods.

Abstract: We propose an effective permittivity model to homogenize an array of long thin $ϵ$-negative rods arranged in a periodic lattice. It is proven that the effect of spatial dispersion in this electromagnetic crystal cannot be neglected, and that the medium supports dispersionless modes that guide the energy along the rod axes. It is suggested that this effect may be used to achieve subwavelength imaging at the infrared and optical domains. The reflection problem is studied in detail for the case in which the rods are parallel to the interfaces. Full wave numerical simulations demonstrate the validity and accuracy of the new model.

Measurement of the distributions of event-by-event flow harmonics in lead-lead collisions at √SNN = 2.76 TeV with the ATLAS detector at the LHC

Abstract: The distributions of event-by-event harmonic flow coefficients v (n) for n = 2- 4 are measured in = 2.76 TeV Pb + Pb collisions using the ATLAS detector at the LHC. The measurements are performed u ...