Atmosphere/soil exchange processes of importance for molecular soil sciences

Globally the atmosphere/soil exchange can be interpreted as part of the biogeochemical cycles describing the transport of main chemical elements and their gaseous compounds between the compartments of the geosphere. Approaches to monitor and analyze these transport processes are described. The paramount role of Earth’s life, the biosphere, in these processes is emphasized

UV Photoelectron Spectroscopy and Outer Valence Electronic Structure of Dihalobenzenes

The electronic structures of nine dihalobenzenes (C6H4FX; X = Cl, Br, I) have been studied by UV photoelectron spectroscopy (UPS) and assigned by comparison with the reported spectra of monoha-lobenzenes (C6H5X; X = Cl, Br, I). and quantum chemical calculations. Our results show that the fluorine substituent modifies energies of π- and halogen lone pair orbitals to a significant degree depending on its location (topology). We also demonstrate that the inductive effect of fluorine atom on the benzene ring can be readily observed and interpreted

An FTMS Investigation of the Competition between Uranium Oxidation and Ligation Reactions

An unexpected formation of oxidation products in the gas-phase reaction of U+ ions with pyrene and 9-azaphenanthrene in a Fourier transform mass spectrometer is reported. The products and reactions are described, but structures and mechanisms are not discussed

Trends, Distribution and Frequency Analysis of Ozone Data from Three Monitoring Stations in Baton Rouge, Louisiana for the Years 1995 to 2005

Troposphere ozone concentrations exhibit pronounced, characteristic diurnal and seasonal cycles. These cycles are usually well defined. However, additional oscillations also occur; these are generally much smaller in amplitude than the 1-day or 1-year cycles and they might be attributable to anthropogenic influences (e.g., specific man-induced meteorological and chemical influences on an individual monitoring station, periodic maintenance activities, etc.). Indeed, it is possible that the spectral analysis of photochemical pollution data could pinpoint hidden conditions that affect particular monitoring stations. Such an analysis, one based on Fourier transform methods, was applied to long-term data from 3 American monitoring stations. As would be expected, strong signals were found for the 1-day and 1-year periods; however, some weaker signals, ones probably associable with anthropogenic affairs, were also observed. A principal component analysis (PCA) was applied to the transformed data sets in order to identify these periods. Periods of 3.5-days and 7-days, as well as a number of other cycles, were found and can be considered to be markers of anthropogenic influences. European and American data will be compared and the effects of Hurricane Katrina will be examined

Role of Nitrogen Oxides in Ozone Toxicity

The preparation of ozone/nitrogen oxides mixtures in air containing the nitrate radical, their reaction with the unsaturated lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), and the determination of the reaction products in comparison to those obtained from a reaction with only ozone in air by MALDI-FTMS is described. The results indicate the importance of nitrate radical in ozone toxicity

Proton Affinities of Nitrogen Oxyradicals

The proton affinities (PA\u27s) of nitric oxide (NO), nitrogen dioxide (NO2), nitric acid (HNO3) as well as those of the cis- and trans-hydrogenhyponitrite (HONNO) and cis- and trans-dioxodinitrate (ONNO–) radicals were calculated by semi-empirical quantum mechanical calculations (standard Gaussian-2 procedure). The PA calculated values of NO (518.8 kJ mol–1), NO2 (580.5 kJ mol–1) and HNO3 (746.0 kJ mol–1) agree with the experimental values. The PA values for the NO3, ONNO– and HONNO radicals were calculated and adjusted to 580, 1330 and 770 kJ mol–1, respectively

Role of Nitrogen Oxides in Ozone Toxicity

The preparation of ozone/nitrogen oxides mixtures in air containing the nitrate radical, their reaction with the unsaturated lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), and the determination of the reaction products in comparison to those obtained from a reaction with only ozone in air by MALDI-FTMS is described. The results indicate the importance of nitrate radical in ozone toxicity

On the Proton Affinity of Peroxynitrite and Peroxynitrous Acid

The proton affinity (PA) of peroxynitrite (ONOO-) and peroxynitrous acid (ONOOH) are calculated to be 1440.5 kJ mol-1 and 749.8 kJ mol-1, respectively. Comparison with results for the nitrous, nitric and peroxynitric acid and their anions supports these estimates

Experimental and Human Evidence for Lipocalin-2 (Neutrophil Gelatinase-Associated Lipocalin [NGAL]) in the Development of Cardiac Hypertrophy and heart failure

Background-Cardiac hypertrophy increases the risk of developing heart failure and cardiovascular death. The neutrophil inflammatory protein, lipocalin-2 (LCN2/NGAL), is elevated in certain forms of cardiac hypertrophy and acute heart failure. However, a specific role for LCN2 in predisposition and etiology of hypertrophy and the relevant genetic determinants are unclear. Here, we defined the role of LCN2 in concentric cardiac hypertrophy in terms of pathophysiology, inflammatory expression networks, and genomic determinants. Methods and Results-We used 3 experimental models: a polygenic model of cardiac hypertrophy and heart failure, a model of intrauterine growth restriction and Lcn2-knockout mouse; cultured cardiomyocytes; and 2 human cohorts: 114 type 2 diabetes mellitus patients and 2064 healthy subjects of the YFS (Young Finns Study). In hypertrophic heart rats, cardiac and circulating Lcn2 was significantly overexpressed before, during, and after development of cardiac hypertrophy and heart failure. Lcn2 expression was increased in hypertrophic hearts in a model of intrauterine growth restriction, whereas Lcn2-knockout mice had smaller hearts. In cultured cardiomyocytes, Lcn2 activated molecular hypertrophic pathways and increased cell size, but reduced proliferation and cell numbers. Increased LCN2 was associated with cardiac hypertrophy and diastolic dysfunction in diabetes mellitus. In the YFS, LCN2 expression was associated with body mass index and cardiac mass and with levels of inflammatory markers. The single-nucleotide polymorphism, rs13297295, located near LCN2 defined a significant cis-eQTL for LCN2 expression. Conclusions-Direct effects of LCN2 on cardiomyocyte size and number and the consistent associations in experimental and human analyses reveal a central role for LCN2 in the ontogeny of cardiac hypertrophy and heart failure.Peer reviewe