Epidemic spreading on interconnected networks

Many real networks are not isolated from each other but form networks of networks, often interrelated in non trivial ways. Here, we analyze an epidemic spreading process taking place on top of two interconnected complex networks. We develop a heterogeneous mean field approach that allows us to calculate the conditions for the emergence of an endemic state. Interestingly, a global endemic state may arise in the coupled system even though the epidemics is not able to propagate on each network separately, and even when the number of coupling connections is small. Our analytic results are successfully confronted against large-scale numerical simulations

Notes florístiques

Exposition of the more interesting floristic results obtained in botanical excursions, that took place during last years, concerning particularly to Conca de Barbera, in the North part of the province of Tarragona . It's interesting to remark the finding of the second know Catalonian locality of Orchis purpurea Huds. and the finding of Arenaria modesta Duf. var. modesta, 80 Km. far from this preceding records. Some new extreme localities are also pointed out for the Catalonian area of Orchis longibracteata Biv., and Euphorbia nevadensis Boiss. et Reut. subsp. aragonensis (Loscos et Pardo ) 0. Bolòs et Vigo var. aragonensis (Loscos et Pardo) 0. Bolòs et Vigo, and Alyssum lapeyrousianum Jord. var. angustifolium (Willk.) 0. Bolòs et Vigo, etc. In all cases, the localization is indicated according U.T.M. grid

Dues Localitats catalanes de "Cenchrus incertus" M. A. Curtis, gramínia nova per a la Península Ibèrica

Two records from Catalonia of an American grass (Cenchrus incertus M. A. Curtis) are reported. They are the first Iberian records and, probably, the first European records too

Notes sobre flora al·lòctona

The authors present some additions to synanthropic flora of the Catalonian countries. Several considerations about the distribution, origine, migration and phytocoenological adscription of certain species are also given