Information on cell size is central to studies of phytoplankton ecology, yet in situ measurements of particle size distribution remain a challenge. The LISST‐100 (Laser In Situ Scattering and Transmissometry; Sequoia Scientific, Inc.) is one of few commercially available instruments that provide autonomous measurements of size distributions of suspended particles in situ. Its capability to size phytoplankton needs to be evaluated, however, for two reasons. First, size is not measured directly; rather, information on size is obtained from near‐forward scattering measurements that are inverted to obtain size distributions. The inversion assumes that particles are homogeneous spheres. Phytoplankton, however, display a wide range of cell shapes and their scattering behavior is likely to be different from that of spheres. Second, the LISST‐100 was originally designed for sediments and its inversion assumes an index of refraction typical of inorganic particles. We compared size and volume concentration distributions obtained by the LISST‐100 to those derived via microscopy for phytoplankton cultures of different cell sizes and shapes. Results demonstrate the success of the LISST‐100 in measuring size and volume concentrations of cells with a cell aspect ratio that is close to 1 and illustrate its limitations when nonspherical cells are present in the sample. Uses of the LISST‐100 in laboratory and field studies are discussed in light of the results from this study.

a b s t r a c tThis paper reviews the current socio-cultural and political state of cycling in Brazil and the policies and activities over recent years that have aimed to reverse its marginalisation. In particular it focuses on the city of Pelotas in the southern state of Rio Grande do Sul and the significant societal and material transformations that are causing conflict and dissonance in relation to the future role of cycling on city streets. Using a combination of empirical evidence from existing literature; a focus group with members of the cycling stakeholder forum; interviews with planning officials whilst observing cycle infrastructure; interviews with participants whilst taking part in a 'protest' bicycle ride (bicicletada); and on street intercept interviews with cycle commuters, this paper highlights the tensions, conflicts, aspirations and imaginaries of a city grappling with significant growth and urban transformation.

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This work addresses the design and configuration of a Eulerian sediment trap mooring array, which was deployed at the shelf edge (z m ≈ 140 m) 80 km off Cabo Frio, SE-Brazil (23° S). The site was subject to interplay between the Tropical Waters (TW) of the Brazil Current (BC), intrusions from the South Atlantic Central Waters (SACW), which are the source of upwelling in the region, and other oceanographic processes. Detailed computations were used to optimize the total weight, buoyancy balance, and maximum acceptable tilt to avoid hydrodynamic bias in the trapping efficiency and array adaptation to the local oceanographic conditions with the assistance of Matlab and Muringa programs and Modular Ocean Model 4.0 (MOM; i.e., to assert the vertical distribution of the meridional current component). The velocity range of the current component was determined by short term measurements to be between 0.1 and 0.5 m/s. Projections led to a resulting minimum anchor weight of 456 kg. The necessary line tension was ascertained by using the appropriate distribution of a series of buoys along the array, which finally attained a high vertical load of 350 kg because of the attached oceanographic equipment. Additional flotation devices resulted in a stable mooring array as reflected by their low calculated tilt (2.6° ± 0.6°). A low drag of 16 N was computed for the maximum surface current velocity of 0.5 m/s. The Reynolds number values ranged from 4 x 10 4 to 2 x 10 5 and a cone-trap aspect ratio of 1.75 was used to assess the trap sampling efficiency upon exposure to different current velocities.

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