Sea urchins (Echinodermata: Echinoidea) generally possess an intricate jaw apparatus that incorporates five teeth. Although echinoid teeth consist of calcite, their complex internal design results in biomechanical properties far superior to those of inorganic forms of the constituent material. While the individual elements (or microstructure) of echinoid teeth provide general insight into proce...

We assessed the influence of rock cavities, or pits, on the growth dynamics and behavior of the purple sea urchin, Strongylocentrotus purpuratus. In a paired-designed, laboratory experiment, sea urchins were assigned to sandstone blocks that were either 'Flat' or had a 'Pit' drilled into the center. At the start, both groups were approximately the same shape and size. In just 2 months, the shap...

A basal zone, tens of meters thick, of debris-laden ice was observed in Kamb Ice Stream, West Antarctica, using a video camera lowered into boreholes made by hot-water drilling. The debris content varies, sometimes abruptly, forming a sequence of layers that reflect the complex history of fast ice flow and bed interaction. In most parts, the concentration of debris is low, a few percent by weig...

Abstract Thwaites Glacier (TG) plays an important role in future sea-level rise (SLR) contribution from the West Antarctic Ice Sheet. Recent observations show that TG is losing mass, and its grounding zone retreating. Previous modeling has produced a wide range of results concerning whether, when, how rapidly further retreat will occur under continued warming. These differences arise at least p...

An earlier developed, first principles hydrodynamic model of gas-fluidized beds has been employed to study theoretically bubble formation at a single orifice in a two-dimensional bed. For several orifice discharge rates, theoretically predicted bubble sizes, formation times and shapes have been compared with experimental data obtained from triggered photographs. Besides, the present experimenta...

A design study has been made of a wave energy converter in the form of a heaving buoy reacting against an internal moving mass. Phase control has been obtained by modulating the stiffness of the spring governing the moving mass. Promising results, agreeing closely with linear theory, have been obtained with two shapes of buoy. Mean annual captures of the order of 2OOW/tonne in a typical South U...

Recent advances in computer technology have tremendously increased the use of functional data, whose graphical representation can be infinite-dimensional curves, images or shapes. This article describes four methods for visualizing functional time series using an R add-on package. These methods are demonstrated using age-specific Australian fertility data from 1921 to 2006 and monthly sea surfa...

Recent advances in computer technology have tremendously increased the usage of functional data, whose graphical representation can be infinite-dimensional curves, images or shapes. This article aims to describe four methods for visualizing functional time series using an R add-on package. These methods are demonstrated using the age-specific Australian fertility data from 1921 to 2006 and mont...

we measured the impacts of coastal modification on beach erosion and beach retreat conditions, selecting the miankaleh region as an example of a complex high-pressure free zone with high levels of engineering and tourism activity. nine sampling transects, stretching from the shoreline to a 10 meter depth, were defined and 36 sediment samples were collected from the sea bed at depths of 1, 3, 5,...