SUMMARY1. In rabbit citrated platelet-rich plasma, the changes in shape of the platelets produced by adenosine diphosphate (ADP) or 5-hydroxytryptamine (5-HT) were observed by photometric and volumetric techniques and by measurements of platelet images on electron micrographs either directly or with an image analysing computer. This permitted the indirect manifestations of the shape changes to be correlated with the morphological features responsible for them, i.e. transformation of disks to more spherical forms and extrusion of blebs and spikes.2. Following the addition of ADP, an initial brief peak in the light scattering records was associated with marked but transient irregularities in the surface of the platelets. These effects were absent when the other shape changes were produced by 5-HT.3. When the optical manifestations of the shape changes induced by ADP were reversed by the addition of antagonists adenosine triphosphate, 2-chloroadenosine or prostaglandin E1, the morphological changes were reversed by a diminution in the number of spikes and the conversion of spherical platelet bodies to a more discoid form.4. The volume of extracellular plasma trapped between platelets sedimented by centrifugation was proportional to the number of spikes which they extruded. Under all conditions, the volume of the platelets themselves remained remarkably constant at approximately 5 x 10-9 ,ul./platelet.5. Addition of a calcium chelating agent alone produced a rapid persistent alteration in the optical properties of platelet-rich plasma. The magnitude of this alteration was proportional to chelator concentration but greater in some plasmas than in others. Similar optical effects were produced when the calcium concentration * Present address:

In the final decades of the nineteenth century, concern was building about the status of migratory bird populations in North America. In this literature review, we describe how that concern led to a landmark conservation agreement in 1916, between the United States and Great Britain (on behalf of Canada) to conserve migratory birds shared by Canada and the United States. Drawing on published literature and our personal experience, we describe how subsequent enabling acts in both countries gave rise to efforts to better estimate population sizes and distributions, assess harvest rates and demographic impacts, design and fund landscape-level habitat conservation initiatives, and organize necessary political and regulatory processes. Executing these steps required large-scale thinking, unprecedented regional and international cooperation, ingenuity, and a commitment to scientific rigor and adaptive management. We applaud the conservation efforts begun 100 years ago with the Migratory Bird Treaty Convention. The agreement helped build the field of wildlife ecology and conservation in the twentieth century but only partially prepares us for the ecological and social challenges ahead. Ó 2017 The Wildlife Society.

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People eat meals rather than nutrients or food groups. Plate size may influence meal size, meal composition, and food type. To examine effects of plate size on meals, we developed a method we label plate mapping. A quasi-experimental study asked university students to accurately draw what they would like to eat for dinner on either a 9″ or 11″ paper plate. Coding plate drawings for total meal size revealed that students drew an average of 26% more food on larger plates. When plates were coded for meal composition we found that the biggest three food portions drawn by students were bigger on 11″ plates, with 70% of the overall difference in food area occurring in the biggest food. Participants drew bigger portions of vegetables on larger plates, while other food types showed little change in mean size. Gender moderated plate sensitivity for food types: women drew 36% bigger vegetable portions than men on larger plates. Smaller plates may lead to smaller meal sizes, but plate size may differentially influence composition of meals for men and women. These findings suggest plate mapping can be used to reflect meal conceptualizations and assess sensitivity to plate size.