Foraging Behavior under Starvation Conditions Is Altered via Photosynthesis by the Marine Gastropod, Elysia clarki

It has been well documented that nutritional state can influence the foraging behavior of animals. However, photosynthetic animals, those capable of both heterotrophy and symbiotic photosynthesis, may have a delayed behavioral response due to their ability to photosynthesize. To test this hypothesis we subjected groups of the kleptoplastic sea slug, Elysia clarki, to a gradient of starvation treatments of 4, 8, and 12 weeks plus a satiated control. Compared to the control group, slugs starved 8 and 12 weeks displayed a significant increase in the proportion of slugs feeding and a significant decrease in photosynthetic capability, as measured in maximum quantum yield and [chl a]. The 4 week group, however, showed no significant difference in feeding behavior or in the metrics of photosynthesis compared to the control. This suggests that photosynthesis in E. clarki, thought to be linked to horizontally-transferred algal genes, delays a behavioral response to starvation. This is the first demonstration of a link between photosynthetic capability in an animal and a modification of foraging behavior under conditions of starvation

Fluorescent Microangiography Is a Novel and Widely Applicable Technique for Delineating the Renal Microvasculature

Rarefaction of the renal microvasculature correlates with declining kidney function. However, current technologies commonly used for its evaluation are limited by their reliance on endothelial cell antigen expression and assessment in two dimensions. We set out to establish a widely applicable and unbiased optical sectioning method to enable three dimensional imaging and reconstruction of the renal microvessels based on their luminal filling. The kidneys of subtotally nephrectomized (SNx) rats and their sham-operated counterparts were subjected to either routine two-dimensional immunohistochemistry or the novel technique of fluorescent microangiography (FMA). The latter was achieved by perfusion of the kidney with an agarose suspension of fluorescent polystyrene microspheres followed by optical sectioning of 200 µm thick cross-sections using a confocal microscope. The fluorescent microangiography method enabled the three-dimensional reconstruction of virtual microvascular casts and confirmed a reduction in both glomerular and peritubular capillary density in the kidneys of SNx rats, despite an overall increase in glomerular volume. FMA is an uncomplicated technique for evaluating the renal microvasculature that circumvents many of the limitations imposed by conventional analysis of two-dimensional tissue sections

International Human Resource Management in the Introductory HRM Course

This paper explores the extent to which students in the introductory HRM course in US institutions are likely to be exposed to information on international and cross-cultural aspects of HRM. Two methods are used: (1) an analysis of international content in fifteen popular introductory HRM textbooks and (2) a survey of professors teaching introductory HRM. The vast majority of responding instructors said their classes got some exposure to international issues in HRM, and most introductory texts included some relevant content. Critiques of international boxed features and dedicated IHRM chapters are provided, and suggestions for improving the quality and depth of IHRM content in introductory textbooks are made

Scanning Electron Microscopy of Blood Vascular Corrosion Casts in Mammals

In this chapter, we will describe the standard technical protocols used to obtain blood vascular cast for the study with SEM, as well as we will briefly review the recent advances in the observation of vascular network through the use of this tool, and its application in the study of angiogenesis mainly according to our experience in the mammalian ovary