Controlling the Size of Popcorn

We present a thermo-statistical model of popcorn production and propose a way to control the final size of the popcorn by monitoring only the chamber pressure.Comment: 6 pages; revision (typo and minor content corrections

Does mate-guarding give non-territorial birds the chance to settle?

Territory defence has been suggested to serve as a means of preventing extrapair copulations. This hypothesis predicts that territory size is largest during the fertile period, and hence at this time few new territory settlements are expected. I show that Great Tits Parus major show a peak in new territory settlements in between adjacent territories precisely at the time other pairs start egg-laying. These newly settled individuals were mostly known as floaters in the area, and did not seem to be paired before they settled. This observation is in contrast with the territory defence to prevent EPC's hypothesis. I hypothesise that males have to trade-off territory defence and mateguarding, enabling new birds to settle at the time males mate guard.</p

Sourcing and Evaluating the Use of Detritus as a Supplementary Diet for Bivalve Aquaculture Using Stable Isotopes and Fatty Acid Biomarkers

Detritus is a ubiquitous component of ecosystems and an important fuel for secondary production. Due to the extractive nature of bivalve aquaculture, detritus is often incorporated into carrying capacity and growth models for cultured bivalves. However, despite the complexity and difficulty in obtaining direct measurements, detritus is often treated as a homogeneous food source in models. Further understanding the role detritus plays in the diet of cultured bivalves could lead to more comprehensive and accurate models as well as more informed site selection for growers. The purpose of this study was to assess the abundance, bioavailability, and contribution of detritus to the diet of a commercially important bivalve (Mytilus edulis) in a northern temperate bay (Saco Bay, ME USA) using a combination of lipid fatty acid biomarkers and stable isotopes (δ13C and δ15N). Both macroalgal (6.9 ± 0.1%) and vascular plant (4.8 ± 0.1%) detritus contributed to the particulate organic matter of Saco Bay and could supplement essential fatty acids (FA) or their precursors to consumers able to digest them. Mussels in Saco Bay may have been limited by the availability of the essential fatty acid 20:5ω3 (EPA) and incorporated macroalgal detritus as a small part (5 to 11%) of their diet. Macroalgae contained large proportions of the essential FAs 20:4ω6 (7 to 18%) and 20:5ω3 (8 to 25%) which may supplement the dietary needs of mussels. The original source of primary production had more influence on the bioavailability of lipid and FAs than the state of decay. The bioavailability of lipid and FAs from Ascophyllum nodosum (9 ± 3%) was significantly lower than that of Spartina alterniflora (56 ± 19%) and Isochrysis galbana (48 ± 2%), likely due to the presence of polyphenols and structural alginates that interfered with lipid solubilization. Although it contains essential FAs and its contribution into the diet of M. edulis suggest macroalgae could be a good supplemental diet for bivalve aquaculture, the concentration of secondary metabolites (\u3e3% wt/wt) and alginates needs to be considered due to their anti-nutritional effects

Increasing the Size of a Piece of Popcorn

Popcorn is an extremely popular snack food in the world today. Thermodynamics can be used to analyze how popcorn is produced. By treating the popping mechanism of the corn as a thermodynamic expansion, a method of increasing the volume or size of a kernel of popcorn can be studied. By lowering the pressure surrounding the unpopped kernel, one can use a thermodynamic argument to show that the expanded volume of the kernel when it pops must increase. In this project, a variety of experiments are run to test the validity of this theory. The results show that there is a significant increase in the average kernel size when the pressure of the surroundings is reduced.Comment: Latex document, 14 pages, 4 figures, 1 page of table