The art of otolith chemistry: interpreting patterns by integrating perspectives

The ability to obtain high-resolution chemical profiles across otoliths has expanded with technological advancements that prompted an explosion of data from diverse taxa in coastal, marine and freshwater systems worldwide. The questions pursued by most otolith chemists fall broadly into six categories: identifying origins, tracking migration, reconstructing environments, quantifying growth or physiology, validating ages and assessing diets. Advances in instrumentation have widened the periodic table of otolith elements, and two-dimensional mapping has further illuminated spatial heterogeneity across these complex structures. Although environmental drivers of observed elemental signatures in otoliths are often assumed to be paramount, multiple intrinsic and extrinsic factors can disrupt simple relationships between an element and a single environmental parameter. An otolith chemical profile is not a direct photograph of an environment, but rather an impressionistic image filtered through the multifaceted experiences of the fish itself. A ‘signal-to-noise’ approach that assesses the relative magnitudes of variation from intrinsic and extrinsic factors on chemical profiles may be a promising way to resolve the factor of interest against the ‘noise’ of others. A robust appreciation of environmental drivers, physiological regulation and calcification dynamics that affect the ability to effectively interpret otolith chemical patterns is necessary to drive the field forward.

The Physical Properties (Enthalpy and Thermal Conductivity) of Mahogany Wood Induced by Pyrolysis Temperature Process

The recent work found the physical properties that greatly affected the transport phenomena; enthalpy values and thermal conductivity values in the pyrolysis process. In the previous work, it was assumed as constant variable. Meanwhile, there were a dependence between the variables and the pyrolysis temperature. Then, it would be calculated both physical properties by using bomb calorimeter and thermal conductivity testing apparatus.In the experimental runs, biomass was shaped in the form of needle particles about 1 μm and run 3 hours to produce char and tar yields. It was carried out at a temperature setting from 250°C to 800°C. To support analysis of the thermal conductivity values, the char yields were visualized by using direct photograph and SEM by 3000 times magnification to investigate the char quality based on the color and the structure of char material imaging their porrosities. The results showed that the entalpy values of char increased with the increasing of pyrolysis temperatures, however, the enthalpy values of tar inclined up to temperature of 500°C. Afterward, it decreased for the reason that the biomass was decomposed gas products in secondary reaction. Another result presented the thermal conductivity increased up to 500°C then it reached almost constant values. The increasing of the thermal conductivity values due to carbon and porosity of char.

THE INTERNAL VELOCITY FIELD IN BREAKING WAVES

As far as is known, the results presented here are the first detailed measurements of the horizontal velocity component inside breaking waves. The field study was originally undertaken in 1960 to determine the presence and strength of mid-depth return flow under shoaling waves (Miller and Zeigler, 1961, 1964). In the course of the experiment, a series of measurements was made very close to the shore. During one tidal cycle, the instruments became exposed to breakers, and continued to operate. A study of the resulting data convinced us that detailed velocity measurements could be made within the natural breaker m the field. Accordingly, a series of runs was made and velocity data collected on breakers ranging from very small to storm size. This data will be presented and discussed in detail in a later portion of this paper. A number of laboratory studies have been made on breakers. These may be placed in three categories for our purposes. The first group includes detailed discussion of observations and sequential figures illustrating the development of breakers. An example is Mason (1951). The second group of papers gives some detail on the structure of breakers and presents, either by direct photograph or sketch of, the trajectory inside the breakers. Examples are Hamada (1951) and Morison and Crooke (1953). The third group of papers presents, in addition to most of the material referred to above, a series of vector maps of the internal velocity under various types of breakers, including both sinusoidal and solitary wave generated breakers. Papers in the third category include Iversen (1951), Larras (1952), and Ippen and Kulin (1955). The latter were of most direct interest to us within the context of the present study.

An Addition to the Senmut-Fresco

On looking lately through a volume (AD. MSS. 29,822) of the manuscript collections bequeathed by the late Mr. Robert Hay to the British Museum, I came across a partly coloured drawing (f. 33) by him, of the well-known wall-painting of Keftian (Minoan Cretan) ambassadors in the tomb of Senmut at Egyptian Thebes. A direct photograph (by Mr. E. R. Ayrton) of this painting was published by me in the Annual for 1903–4 (x. p. 154) and a year later, Dr. W. M. Müller gave us a fine photograph and also a hand-drawn reproduction of it in colour in the first volume of his Egyptological Researches, published by the Carnegie Institute (1906), Plates 5, 6, and 7. These were the first published illustrations of the whole painting as it is now.