(Table 1) Comparison of dive duration and speed of Adélie penguins (Pygoscelis adeliae) equipped with internal and external devices

Bio-logging studies suffer from the lack of real controls. However, it is still possible to compare indirect parameters between control and equipped animals to assess the level of global disturbance due to instrumentation. In addition, it is also possible to compare the behaviour of free-ranging animals between individuals equipped with different techniques or instruments to determine the less deleterious approach. We instrumented Adelie Penguins (Pygoscelis adeliae) with internal or external time-depth recorders and monitored them in parallel with a control group during the first foraging trip following instrumentation. Foraging trip duration was significantly longer in the internally-equipped group. This difference was due to a larger number of dives, reflecting a lower foraging ability or a higher food demand, and longer periods of recovery at the surface. These longer recovery periods were likely to be due to a reduced efficiency to ventilate at the surface, probably because the implanted devices pressurised adjacent organs such as air sacs. Moreover, descent and ascent rates were slightly lower in externally-equipped penguins, presumably because external instrumentation increased the bird drag. Looking at our results, implantation appears more disadvantageous - at least for short-term deployment - than external equipment in Adelie Penguins, while this method has been described to induce no negative effects in long-term studies. This underlines the need to control for potential effects due to methodological aspects in any study using data loggers in free-ranging animals, to minimise disturbance and collect reliable data.

Analyzation of marine snow and fecal pellets collected in sediment trap CBi-2 off Cape Blanc, Mauritania

We analyzed size-specific dry mass, sinking velocity, and apparent diffusivity in field-sampled marine snow, laboratory-made aggregates formed by diatoms or coccolithophorids, and small and large zooplankton fecal pellets with naturally varying content of ballast materials. Apparent diffusivity was measured directly inside aggregates and large (millimeter-long) fecal pellets using microsensors. Large fecal pellets, collected in the coastal upwelling off Cape Blanc, Mauritania, showed the highest volume-specific dry mass and sinking velocities because of a high content of opal, carbonate, and lithogenic material (mostly Saharan dust), which together comprised ~80% of the dry mass. The average solid matter density within these large fecal pellets was 1.7 g cm**-3, whereas their excess density was 0.25 ± 0.07 g cm**-3. Volume-specific dry mass of all sources of aggregates and fecal pellets ranged from 3.8 to 960 µg mm**-3, and average sinking velocities varied between 51 and 732 m d**-1. Porosity was >0.43 and >0.96 within fecal pellets and phytoplankton-derived aggregates, respectively. Averaged values of apparent diffusivity of gases within large fecal pellets and aggregates were 0.74 and 0.95 times that of the free diffusion coefficient in sea water, respectively. Ballast increases sinking velocity and, thus, also potential O2 fluxes to sedimenting aggregates and fecal pellets. Hence, ballast minerals limit the residence time of aggregates in the water column by increasing sinking velocity, but apparent diffusivity and potential oxygen supply within aggregates are high, whereby a large fraction of labile organic carbon can be respired during sedimentation.

Automotive energy efficiency program. Presented papers.

Transportation Department, Office of the Assistant Secretary for Systems Development and Technology, Washington, D.C.

Chord-wise air load distribution : War Dept., Army Air Forces : Navy Dept., Bureau of Aeronautics : Dept. of Commerce, Civil Aeronautics ... /

Tables.

Fluid dynamics and applications,

Reproduced from typewritten copy.

Selected topics in fluid mechanics, Summer session 1946 [New York University?]

Reproduced from typewritten copy.

Investigation of the flow over simple bodies at Mach numbers of the order of 20 /

"It is shown that adequate means are available for calculating inviscid direct and induced pressures on simple axisymmetric bodies at zero angle of attack. The extent to which viscous effects can alter these predictions is indicated. It is also shown that inviscid induced pressures can significantly affect the stability of blunt, two-dimensional flat wings at low angles of attack. However, at high angles of attack, the inviscid induced pressure effects are negligible."

An investigation of the exact solutions of the linearized equations for the flow past conical bodies,

Reproduced from type-written copy.

Augmentation of research and analysis capabilities for timely support of automotive fuel economy activities. Volume II: appendices A through C. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Augmentation of research and analysis capabilities for timely support of automotive fuel economy activities. Volume III: appendix D. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

An experimental study of highway aerodynamic interferences. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

NACA research memorandum.

Description based on: RM no. A6G24 (May 12, 1947); title from cover.

Augmentation of research and analysis capabilities for timely support of automotive fuel economy activities. Volume I: summary. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Evaluation of techniques for reducing in-use automobile fuel consumption. Final report.

National Highway Traffic Safety Administration, Office of Research and Development, Washington, D.C.

Kinetic study of the hypersonic flow past the leading edge of a flat plate.

Vita.