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To better understand the early life history stages of the American lobster Homarus americanus, nutritional and bioenergetic aspects of development have been investigated. These studies focused on physiological and biochemical processes during transitional periods between extrusion of the eggs, hatching, larval development, molting, metamorphosis, and attainment of the juvenile stage. Biochemical changes during embryogenesis reflect catabolism of various substrates for energy. Exposure to different thermal regimes resulted in considerable variation in the rates of utilization of energy substrates during embryogenesis. Embryos raised at elevated temperatures had yolk remaining at the time of hatching. The first three larval stages have similar energy requirements. Lipid is of prime importance and the turnover rate for lipid can be rapid. Weight-specific metabolism increases with successive larval stages, in stage IV lobsters, the dependency on lipid as a substrate is diminished and lipid reserves serve a storage function. Metabolic rates of premolt stage IV lobsters are decreased in comparison with earlier stages. These changes in physiology correlate with changes in the developing midgut gland, specifically with the appearance of droplets of lipid in the lipid-storing cells of the midgut gland of stage IV lobsters. By stage VI, lobsters have energy storage and metabolic patterns similar to those of adults, and the midgut gland has the adult morphology. The transitions from hatching to attainment of the juvenile form are reflected in differences in physiological and biochemical processes that influence food selection and diet.

Background: Technologies for purification of living cells have significantly advanced basic and applied research in many settings. Nevertheless, certain challenges remain, including the robust and efficient purification (e.g., high purity, yield, and sterility) of adherent and/or fragile cells and small cell samples, efficient cell cloning, and safe purification of biohazardous cells. In addition, existing purification methods are generally open loop and exhibit an inverse relation between cell purity and yield. Methods: An automated closed-loop (i.e., employing feedback control) cell purification technology was developed by building upon medical laser applications and laser-based semiconductor manufacturing equipment. Laser-enabled analysis and processing has combined highthroughput in situ cell imaging with laser-mediated cell manipulation via large field-of-view optics and galvanometer steering. Laser parameters were determined for cell purification using three mechanisms (photothermal, photochemical, and photomechanical), followed by demonstration of system performance and utility. Results: Photothermal purification required approximately 10 8 W/cm 2 at 523 nm in the presence of Allura Red, resulting in immediate protein coagulation and cell necrosis. Photochemical purification required approximately 10 9 W/cm 2 at 355 nm, resulting in apoptosis induction over 4 to 24 h. Photomechanical purification

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