These findings will likely provide new insight into the complex mechanisms
involved in calcium homeostasis and hopefully lead to novel preventive and therapeutic approaches.”
“Interaction of carbonate surfaces with water plays GW4869 a crucial role in carbonate nucleation and crystal growth. This study provides experimental evidence for the existence of two different types of water having distinct energetics in amorphous carbonates, MCO3 (M = Ca, Mn, and Mg). The adsorption enthalpy curves obtained using a combination of gas sorption and microcalorimetry show two different energetic regions, which correspond to weakly bound restrictedly mobile and strongly bound rigid H2O components. For weakly bound water, adsorption enthalpies of amorphous calcium carbonate (ACC) (-55.3 +/- 0.9 kJ/mol), amorphous manganese carbonate (AMnC) (-54.1 +/- 0.8 kJ/mol), and amorphous magnesium carbonate (AMgC) (-56.1 +/- 0.4 kJ/mol) fall in the same range, suggesting their interaction modes may be similar in all amorphous phases. Water adsorption enthalpies of crystalline nanocalcite (-96.3 +/- 1 kJ/mol) and nano-MnCO3 (-65.3 +/- 3 kJ/mol) measured selleckchem in previous studies are more exothermic than values for ACC (-62.1 +/- 0.7 kJ/mol) and AMnC
(-54.1 +/- 0.8 kJ/mol) and could provide a driving force for crystallization of ACC and AMnC in the presence of water. The differences in water adsorption behavior between amorphous and naocrystalline material have significant implications for crystal growth, biomineralization, and carbonate geochemistry.”
“The determination of activity-specific energy expenditure of wild animals is key in ecology and CH5183284 Angiogenesis inhibitor conservation sciences. Energy management is crucial for seabirds during the breeding
season when they need to maintain a positive balance between energy intake and the metabolic costs for them and their young. We analysed information from accelerometers to estimate the energy expenditure of Magellanic penguins (Spheniscus magellanicus) foraging at sea during the early chick-rearing period from four Patagonian colonies (i.e. Punta Norte, Bahia Bustamante, Puerto Deseado and Puerto San Julian). We studied how activity-specific energy consumption affected total energy expenditure during foraging and considered how this related to the current status and trends of breeding populations. The derived diving energy expenditure of penguins differed between sites, with inter-colony differences being primarily due to variability during the bottom and ascent phases of the dives: bottom phase energy expenditure was largely determined by the total distances travelled during the search, pursuit, and capture of prey, rather than the time per se allocated to this phase.