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Little Longer (little + longer)
Selected AbstractsDaily to seasonal cross-shore behaviour of quasi-persistent intertidal beach morphologyEARTH SURFACE PROCESSES AND LANDFORMS, Issue 9 2007S. Quartel Abstract In this study, an intertidal bar and trough system on the beach of Noordwijk, The Netherlands was monitored over a 15-month period in order to examine the daily to seasonal sequential cross-shore behaviour and to establish which conditions force or interrupt this cyclic bar behaviour. The beach morphology (bars and troughs) was classified from low-tide Argus video images based on surface composition. From the classified images, time series of the landward boundary of the bar and of the trough were extracted. The time series of the alongshore-averaged boundary positions described sawtooth motion with a period between 1 and 4 months, comprising gradual landward migration followed by abrupt seaward shifts. The abrupt seaward shift appeared to be a morphological reset induced by storm events, which lasted at least 30 h with a large average root-mean-square wave height (,2 m) and offshore surge level (,0·5 m), and a small trough (<20 m wide) in the pre-storm beach morphology. The time series of the boundary positions exhibited very little longer (seasonal) scale variability, but somewhat larger smaller (daily) scale variability. The bar boundary was found to be more dynamic than the trough boundary. Copyright © 2007 John Wiley & Sons, Ltd. [source] Effect of photoperiod on development and growth in a pentatomid bug, Dolycoris baccarumENTOMOLOGICAL SCIENCE, Issue 1 2003Keiji Nakamura Abstract The effect of photoperiod on nymphal development, growth and adult size was examined in a pentatomid bug, Dolycoris baccarum, collected in Osaka (a warm temperate region) and Hokkaido (a subfrigid region), Japan. When insects were reared from eggs at 25°C, the developmental period was long and adult size was large under photoperiods close to the critical photoperiod for the induction of adult diapause. Adults of the Hokkaido population were larger than those of the Osaka population. There was no significant correlation between developmental period and adult size. Insects also showed variation in their growth rate: growth rate was low under photoperiods a little longer than the critical photoperiod for the induction of diapause. The ecological significance of variation in development and growth is discussed. [source] A fine-resolution Pliocene pollen and charcoal record from Yallalie, south-western AustraliaJOURNAL OF BIOGEOGRAPHY, Issue 2 2004Pia Atahan Abstract Aim, This paper aims to reconstruct a high-resolution fire and vegetation history from a period when humans were absent in Australia. This is then used to comment on the frequency of natural fire in high biodiversity heathland, and to compare this with historical fire regime in the same region. Methods, A section of varved sediment covering a period of c. 84 years was taken from Palaeolake Yallalie in south-western Australia. The sediments were separated into approximately single to small multiples of years and then analysed for charcoal, pollen and sediment analysis to reconstruct the environmental conditions at the time. Results, The charcoal record indicates fire recurrence to have been roughly between 5 and 13 years, a little longer than those of the historical period. The pollen record was dominated by Casuarinaceae, Myrtaceae and a large number of Proteaceae species; these are intermixed with Araucariaceae, Nothofagus and Podocarpus. This suggests there was a mix of sclerophyll woodland and a mosaic of rain forest elements, thus conditions must have been wetter, particularly in the summers, compared with today. Conclusions, We assume that fire was most likely confined to the sclerophyll vegetation, and that fire has been a significant feature of the environment long before humans entered Australia. The slightly longer fire recurrence times compared with the present result from the intermittent nature of lightning and wetter summers at the time. [source] Acquisition of double-stranded DNA-binding ability in a hybrid protein between Escherichia coli CspA and the cold shock domain of human YB-1MOLECULAR MICROBIOLOGY, Issue 3 2000Nan Wang Escherichia coli CspA, a major cold shock protein, is dramatically induced upon temperature downshift. As it binds co-operatively to single-stranded DNA (ssDNA) and RNA without apparent sequence specificity, it has been proposed that CspA acts as an RNA chaperone to facilitate transcription and translation at low temperature. CspA consists of a five-stranded ,-barrel structure containing two RNA-binding motifs, RNP1 and RNP2. Eukaryotic Y-box proteins, such as human YB-1, are a family of nucleic acid-binding proteins that share a region of high homology with CspA (43% identity), termed the cold shock domain (CSD). Their cellular functions are very diverse and are associated with growth-related processes. Here, we replaced the six-residue loop region of CspA between the ,3 and ,4 strands with the corresponding region of the CSD of human YB-1 protein. The resulting hybrid protein became capable of binding to double-stranded DNA (dsDNA) in addition to ssDNA and RNA. The dsDNA-binding ability of an RNP1 point mutant (F20L) of the hybrid was almost unchanged. On the other hand, the dsDNA-binding ability of the hybrid protein was abolished in high salt concentrations in contrast to its ssDNA-binding ability. These results indicate that the loop region between the ,3 and ,4 strands of Y-box proteins, which is a little longer and more basic than that of CspA, plays an important role in their binding to dsDNA. [source] | ||||||||||