Palynological analyses from exposed palaeolacustrine deposits located at the flanks of Damavand volcano, in the central AlborzMountains in Northern Iran, provide a broad idea of the temporal variation of vegetation according to climate changes during a rangeof limited time intervals during the Quaternary period. This research reveals that the regional vegetation of the study area had been asemi...

expanded abstract introduction in general, loess sediments are one of the most widespread forms of eolian sediments. during the past few decades, loess stratigraphy studies played key role in global climate changes. these sediments are usually yellowish in color and silt makes 70 to 90 percent of it volume. in iran, loesses outcrop often in northeast of south caspian sea. the previous studies r...

In this paper, a new construction method of quaternary sequences of even period 2N having the ideal autocorrelation and balance properties is proposed. These quaternary sequences are constructed by applying the inverse Gray mapping to binary sequences of odd period N with the ideal autocorrelation. Autocorrelation distribution of the proposed quaternary sequences is derived. These sequences can...

introduction in spite of its short time period compared with the earth long evolution history, quaternary has had a significant effect on the final formation of the landforms and vital resources. it is the final analysis of these levels and fully dependent on the earth genetic diseases and, above all, significant climate changes that have happened during this period. gavkhouni basin morphologic...

The terrestrial Quaternary stratigraphic record of British Columbia is largely a product of brief depositional events separated by long periods of nondeposition and erosion. Thick, stratified Quaternary sediments are present mainly in valleys and coastal lowlands and accumulated during periods of growth and decay of the Cordilleran Ice Sheet. At glacial maxima, till was deposited over large are...

BACKGROUND The origin of extraordinarily rich biodiversity in tropical forests is often attributed to evolution under stable climatic conditions over a long period or to climatic fluctuations during the recent Quaternary period. Here, we test these two hypotheses using Dracaena cambodiana, a plant species distributed in paleotropical forests. METHODS WE ANALYZED NUCLEOTIDE SEQUENCE DATA OF TW...

The lactic acid bacteria (LAS) play an important role in the production of fermented foods. The development of concentrated cultures of LAS, for inoculating the production vat directly (bulk starters), has eliminated many problems traditionally involved in their preparation and maintenance by the food industry. For industrial use, LAS are often preserved in a frozen or dried form, the latter pr...