Climatically driven loss of calcium in steppe soil as a sink for atmospheric carbon

During the last several thousand years the semi‐arid, cold climate of the Russian steppe formed highly fertile soils rich in organic carbon and calcium (classified as Chernozems in the Russian system). Analysis of archived soil samples collected in Kemannaya Steppe Preserve in 1920, 1947, 1970, and fresh samples collected in 1998 indicated that the native steppe Chernozems, however, lost 17–28 kg m−2 of calcium in the form of carbonates in 1970–1998. Here we demonstrate that the loss of calcium was caused by fundamental shift in the steppe hydrologic balance. Previously unleached soils where precipitation was less than potential evapotranspiration are now being leached due to increased precipitation and, possibly, due to decreased actual evapotranspiration. Because this region receives low levels of acidic deposition, the dissolution of carbonates involves the consumption of atmospheric CO2. Our estimates indicate that this climatically driven terrestrial sink of atmospheric CO2 is ∼2.1–7.4 g C m−2 a−1. In addition to the net sink of atmospheric carbon, leaching of pedogenic carbonates significantly amplified seasonal amplitude of CO2 exchange between atmosphere and steppe soil

Portable Flux Tower Deployments Field Campaign Report

Contents Acronyms and Abbreviations...................................................................... iii 1.0 Summary ....................................................... 1 2.0 Results ........................................... 1 3.0 Publications and References ................................................. 2 4.0 Lessons Learned ....................................................................

Color Variability of the Blazar AO 0235+16

Multicolor (UBVRIJHK) observations of the blazar AO 0235+16 are analyzed. The light curves were compiled at the Turin Observatory from literature data and the results of observations obtained in the framework of the WEBT program (http://www.to.astro/blazars/webt/). The color variability of the blazar was studied in eight time intervals with a sufficient number of multicolor optical observations; JHK data are available for only one of these. The spectral energy distribution (SED) of the variable component remained constant within each interval, but varied strongly from one interval to another. After correction for dust absorption, the SED can be represented by a power law in all cases, providing evidence for a synchrotron nature of the variable component. We show that the variability at both optical and IR wavelengths is associated with the same variable source.Comment: 11 pages, 9 figures, 4 tables, accepted for publication in Astronomy Report

A sound-producing voice prosthesis

Mahieu, H.F. [Promotor]Festen, J.M. [Copromotor]Verdonck-de Leeuw, I.M. [Copromotor

Biologically Enhanced Carbon Sequestration: Research Needs and Opportunities

Fossil fuel combustion, deforestation, and biomass burning are the dominant contributors to increasing atmospheric carbon dioxide (CO{sub 2}) concentrations and global warming. Many approaches to mitigating CO{sub 2} emissions are being pursued, and among the most promising are terrestrial and geologic carbon sequestration. Recent advances in ecology and microbial biology offer promising new possibilities for enhancing terrestrial and geologic carbon sequestration. A workshop was held October 29, 2007, at Lawrence Berkeley National Laboratory (LBNL) on Biologically Enhanced Carbon Sequestration (BECS). The workshop participants (approximately 30 scientists from California, Illinois, Oregon, Montana, and New Mexico) developed a prioritized list of research needed to make progress in the development of biological enhancements to improve terrestrial and geologic carbon sequestration. The workshop participants also identified a number of areas of supporting science that are critical to making progress in the fundamental research areas. The purpose of this position paper is to summarize and elaborate upon the findings of the workshop. The paper considers terrestrial and geologic carbon sequestration separately. First, we present a summary in outline form of the research roadmaps for terrestrial and geologic BECS. This outline is elaborated upon in the narrative sections that follow. The narrative sections start with the focused research priorities in each area followed by critical supporting science for biological enhancements as prioritized during the workshop. Finally, Table 1 summarizes the potential significance or 'materiality' of advances in these areas for reducing net greenhouse gas emissions

The Stellar Content of the Polar Rings in the Galaxies NGC 2685 and NGC 4650A

We present the results of stellar photometry of polar-ring galaxies NGC 2685 and NGC 4650A, using the archival data obtained with the Hubble Space Telescope's Wide Field Planetary Camera 2. Polar rings of these galaxies were resolved into ~800 and ~430 stellar objects in the B, V and Ic bands, considerable part of which are blue supergiants located in the young stellar complexes. The stellar features in the CM-diagrams are best represented by isochrones with metallicity Z = 0.008. The process of star formation in the polar rings of both galaxies was continuous and the age of the youngest detected stars is about 9 Myr for NGC 2685 and 6.5 Myr for NGC 4650A.Comment: 21 pages, 9 figures, AJ 2004 February, accepte

Severe neonatal enterovirus infection in twins with different outcomes:A case report

Enteroviruses are among the most common causes of acute viral illness worldwide, and in neonates, the clinical course of these infections is heterogeneous. Severe complications, such as myocarditis, are associated with high mortality rates. In this case report, we present the clinical course of premature twins born at 35 weeks of gestational age, suffering from a severe neonatal enterovirus infection with cardiac involvement, which proved fatal in one of the twins. This course led to prompt identification in the other twin and facilitated timely transfer to a neonatal intensive care unit with neonatal hemodynamic expertise, and facilitated the timely transfer to a neonatal intensive care nit with hemodynamic expertise and immediate availability of AZCMO would it have been indicated. Early supportive therapy in the other twin contributed to a positive outcome. Therefore, we emphasize the importance of early recognition in averting adverse consequences. As a recommendation, we propose routine screening of enterovirus in viral panels for febrile newborns.</p