Early life recorded in archean pillow lavas

Pillow lava rims from the Mesoarchean Barberton Greenstone Belt in South Africa contain micrometer-scale mineralized tubes that provide evidence of submarine microbial activity during the early history of Earth. The tubes formed during microbial etching of glass along fractures, as seen in pillow lavas from recent oceanic crust. The margins of the tubes contain organic carbon, and many of the pillow rims exhibit isotopically light bulk-rock carbonate delta13C values, supporting their biogenic origin. Overlapping metamorphic and magmatic dates from the pillow lavas suggest that microbial life colonized these subaqueous volcanic rocks soon after their eruption almost 3.5 billion years ago.     

Ferruginous conditions dominated later neoproterozoic deep-water chemistry

Earth's surface chemical environment has evolved from an early anoxic condition to the oxic state we have today. Transitional between an earlier Proterozoic world with widespread deep-water anoxia and a Phanerozoic world with large oxygen-utilizing animals, the Neoproterozoic Era [1000 to 542 million years ago (Ma)] plays a key role in this history. The details of Neoproterozoic Earth surface oxygenation, however, remain unclear. We report that through much of the later Neoproterozoic (<742 +/- 6 Ma), anoxia remained widespread beneath the mixed layer of the oceans; deeper water masses were sometimes sulfidic but were mainly Fe2+-enriched. These ferruginous conditions marked a return to ocean chemistry not seen for more than one billion years of Earth history.     

Molecular layering of fluorinated ionic liquids at a charged sapphire (0001) surface

Room-temperature ionic liquids (RTILs) are promising candidates for a broad range of "green" applications, for which their interaction with solid surfaces plays a crucial role. In this high-energy x-ray reflectivity study, the temperature-dependent structures of three ionic liquids with the tris(pentafluoroethyl)trifluorophosphate anion in contact with a charged sapphire substrate were investigated with submolecular resolution. All three RTILs show strong interfacial layering, starting with a cation layer at the substrate and decaying exponentially into the bulk liquid. The observed decay length and layering period point to an interfacial ordering mechanism, akin to the charge inversion effect, which is suggested to originate from strong correlations between the unscreened ions. The observed layering is expected to be a generic feature of RTILs at charged interfaces.     

Matrilin-1 expression is increased in the vertebral column of Atlantic salmon (<Emphasis Type="Italic">Salmo salar</Emphasis> L.) individuals displaying spinal fusions

We have previously characterized the development of vertebral fusions induced by elevated water temperature in Atlantic salmon. Molecular markers of bone and cartilage development together with histology were used to understand the complex pathology and mechanism in the development of this spinal malformation. In this study, we wanted to use proteomics, a non-hypothetical approach to screen for possible new markers involved in the fusion process. Proteins extracted from non-deformed and fused vertebrae of Atlantic salmon were therefore compared by two-dimensional electrophoresis (2DE) and MALDI-TOF analysis. Data analysis of protein spots in the 2DE gels demonstrated matrilin-1, also named cartilage matrix protein, to be the most highly up-regulated protein in fused compared with non-deformed vertebrae. Furthermore, real-time PCR analysis showed strong up-regulation of matrilin-1 mRNA in fused vertebrae. Immunohistochemistry demonstrated induced matrilin-1 expression in trans-differentiating cells undergoing a metaplastic shift toward chondrocytes in fusing vertebrae, whereas abundant expression was demonstrated in cartilaginous tissue and chordocytes of both non-deformed and fused vertebrae. These results identifies matrilin-1 as a new interesting candidate in the fusion process, and ratify the use of proteomic as a valuable technique to screen for markers involved in vertebral pathogenesis.     

Use of threshold serum and milk ketone concentrations to identify risk for ketosis and endometritis in high-yielding dairy cows

OBJECTIVE: To use threshold concentrations of acetone and beta-hydroxybutyrate in milk and serum, respectively; identify risk for ketosis and endometritis; and assess analyses of blood and milk samples as predictors of risk for ketosis in high-yielding dairy cows. ANIMALS: 90 multiparous Holstein cows. PROCEDURE: At intervals before and after parturition, blood samples were obtained for determination of glucose, nonesterified fatty acids, leptin, insulin, insulin-like growth factor-1, and beta-hydroxybutyrate concentrations. Samples of milk were obtained at similar intervals after parturition for determination of fat content and concentrations of acetone, protein, and lactose. Reproductive examination of each cow was performed weekly. RESULTS: For each cow, threshold concentrations of acetone and beta-hydroxybutyrate were calculated as 75th and 90th percentiles of maximum postpartum concentrations of acetone in milk (0.40 and 0.87 mmol/L) and beta-hydroxybutyrate in serum (2.30 and 3.51 mmol/L). Significant decrease in milk production (442 to 654 kg of energy-corrected milk/305-day period per cow) was associated with acetone or beta-hydroxybutyrate in excess of threshold values. Milk acetone concentrations > 0.40 mmol/L were associated with 3.2 times higher risk for endometritis. Low plasma glucose, high serum beta-hydroxybutyrate, and high milk acetone concentrations during week 1 after parturition were indicators of increased risk for ketosis later during lactation. CONCLUSIONS AND CLINICAL RELEVANCE: Determination of milk acetone concentration during the week after parturition may identify cows at risk for ketosis and endometritis; with appropriate interventions, development of disease and production losses may be reduced.