Ayatollah Ruhollah Khomeini urged Iranians yesterday to rejoice in their final break with the “ world-devouring plunder’’ America, and the Tehran gov­ ernment began mobilizing the people for a “ holy war” of belt-tightening and possible rationing to grapple with econ­ omic woes. President Abolhassan BaniSadr declared there was “ no reason to worry” about the U.S. econom ic em bargo ag a in st I...

Introduction: Highland paterae [1-2] represent one of the most distinctive landforms on the Martian surface. The term patera (paterae if plural) was originally applied to any large, flat-floored depression with irregular margins identified in Mariner 9 and Viking imagery and included volcanoes as well as impact craters [3]. However, highland paterae represent an individual class of patera that ...

The impact of volcanic eruptions on forest ecosystems can be investigated using dendrochronological records. While long-range effects are usually mediated by decreased air temperatures, resulting in frost rings or reduced maximum latewood density, local effects include abrupt suppression of radial growth, occasionally followed by greater than normal growth rates. Annual rings in Mexican mountai...

Abstract We studied the rupicolous and dioecious species of Bakerantha (Bromeliaceae) that grow as narrow endemics in central-eastern Mexico. aimed to describe spatio-temporal framework which its originated using a phylogeographic population genetics approach. carried out analyses on 29 populations five spp., plastid nuclear DNA sequences. The data were used analyse their diversity, genetic str...