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Objective:Measurement of aldosterone is the cornerstone in Primary aldosteronism (PA) workup, for both screening and final diagnosis (as confirmatory test). Albeit several automated aldosterone chemiluminescent assays have become recently available as reliable alternatives to the well-established ra

This study focuses on the biological and morphological development of humus profiles in forested Italian Alpine soils as a function of climate. Humus form description, systematic investigation of microannelid communities and polyphasic biochemical fingerprinting of soil microbial communities (denaturing gradient gel electrophoresis (DGGE) and phospholipid fatty acid analysis (PLFA)) were performed to compare sites differing in mean annual temperature due to different altitude and exposure. Although the soil biota showed complex responses, several differences in soil biological properties seem to be due to thermal differences. Although soil acidity also determines biological properties, it is not a state factor but rather influenced by them. The thickness of the organic layer and the acidification of the subjacent mineral horizon increased under cooler conditions (north-exposure; higher altitude), whereas the thickness of the A horizon inversely decreased. Species richness of microannelid assemblages was higher under warmer conditions (south-exposure; lower altitude) and the vertical distribution of microannelids shifted along the gradient to lower temperatures from predominant occurrence in the mineral soil to exclusive occurrence in the organic layer. Microbial biomass (total PLFA) was higher at the cooler sites; the prevalence of Gram-negative bacteria could be ascribed to their better adaptation to lower temperature, pH and nutrient contents. The δ13C signatures of the PLFA markers suggested a lower decomposition rate at the cooler sites, resulting in a lower respiratory loss and an accumulation of weakly decomposed organic material. DGGE data supported the PLFA results. Both parameters reflected the expected thermal sequence. This multidisciplinary case study provided indications of an association of climate, mesofauna and microbiota using the humus form as an overall link. More data are however needed and further investigations are encouraged.

l-Methyl-cis, cis-cyclooctadiene-1,5 was obtained by mixed butadiene-isoprene dimerization in the presence of a catalyst prepared by treating nickel acetylacetonate with lithium boron hydride in the presence of triphenyl phosphite. In analogy with cis, cis-cyclooctadiene-1,5, methyleyclooctadiene can be polymerized, in the presence of the Al(iC4H9)3 + TiCl4 eatalytic system (molar ratio of Al to Ti = 0.5), to an essentially saturated product. Also in this case a transannular polymerization of the following type occurs: In the terpolymerization with ethylene and propylene, on the contrary, methyl cyclo-octadiene reacts, in the presence of catalysts prepared from vanadium and alkyl aluminum compounds, by opening of the nonsubstituted double bond. The IR spectra of the monomer and of the polymers are here described.

Two soil sequences in northern Italy (Val di Fiemme and Val Genova) along an elevational gradient ranging from moderate (950 m a.s.l.) to high alpine (2440 m a.s.l.) climate zones were investigated with respect to element losses (Ca, Mg, K, Na, Fe, Al, Si, Mn) and development of clay minerals. Soils formed on paleo-rhyolitic parent material in Val di Fiemme and on tonalitic-granodioritic morainic material in Val Genova. All the soils have a similar age (∼12,000 y) and have been classified as Podzols. The soils are very acid and the pH values tend to increase with decreasing altitude. Podzolization processes were most intense in the range of the subalpine forest up to the timberline (1400–1900 m above sea-level (a.s.l.)). Element leaching was greatest in this range and weathering rates decrease with both higher and lower altitudes. Due to the different lithologies and precipitations between the two valleys, the total amount of chemical weathering was slightly different, although the same trends with altitude could be observed. Imogolite-type materials (ITM) are generally of minor importance. Greater concentrations of ITM were observed in the Bhs or Bs horizons of the Episkeleti-Entic Podzols at the lower altitudes. Iron eluviation was similar in all Podzols while larger amounts of eluviated Al were detected in Val Genova. The pattern of smectite distribution along the climosequences had similarities to the trend of cation losses. The largest amount of low-charge expandable minerals seems to exist in the range of the subalpine forest up to the timberline. The development of clay minerals with a smaller layer charge was more advanced in Podzols on rhyolitic material where smectite could be detected in the Bhs and Bs horizon. Parent material influenced chemical weathering in the soils along the two climosequences and essentially determined the degree of weathering and the formation of clay minerals.

A round 10-in. diameter Hybrid Photodiode (HPD) with spherical entrance window is under development for Cherenkov imaging applications in cosmic ray astronomy. The HPD adopts the fountain focusing electron optics, which, as already demonstrated in the 5 inch Pad HPD, allows for a linear demagnification of the image over practically the full tube diameter. Self-triggering front-end electronics providing also sparse readout capability, has been tested. High-efficiency Rb 2 Te cathodes have been produced on a UV extended borosilicate glass windows with very thin conductive underlayers of Indium Tin Oxide. We report on the design of the 10-in. HPD, the fabrication procedure and first tests of a 5-in. HPD with Rb 2 Te photocathode and 2048 channels.

The formation of clay minerals was investigated in Spodosols developed in the subalpine belt, with similar exposure, climate and age, but deriving from different parent materials. All the soils were classified as Haplic Podzols and showed the characteristic eluviation and illuviation features of Fe, Al and organic carbon. However, varying parent material lithology led to different clay mineral assemblages in the soil. Smectite could be found in the E horizons of soils developed from granodiorite and tonalite materials. Its formation was strongly dependent on the presence of chlorite in the parent material. If nearly no other 2:1 mineral components, such as chlorite, are present in the lower soil horizons, then a residual micaceous mineral becomes the dominant clay mineral. The latter derives from a mica-vermiculite interstratified mineral.

Flexsorb HP is a new, sterically hindered amine-promoted, potassium carbonate-based process for CO2 absorption from gases. Compared to the conventional diethanolamine (DEA) promoted process, it offers considerable capacity and rate advantages. It has outstanding stability toward the corrosion inhibitor V5+, which degrades DEA. Its amine promoter aging resistance is much superior to that of DEA. It can serve as a “drop in” technology that can be used in an existing plant, leading to capacity increase without any equipment modification. For grassroots applications it requires lower investments than DEA-promoted units. ∗ Presented in part at the AIChE 1994 Spring National Meeting, Atlanta, GA.

Two soil profile sequences on paragneiss debris in the Val di Rabbi (Northern Italy) along an altitude gradient ranging from 1200 to 2400 m a.s.l. were studied to evaluate the effect of aspect on the weathering of clay minerals. All the soils had a coarse structure, a sandy texture and a low pH. Greater weathering intensities of clay-sized phyllosilicates (greater content of smectites) were observed in soils on the north-facing slope. On the south-facing slope, smectite was found only in the surface horizon of the soil profile at the highest altitude. Hot citrate treatment of north-facing soils revealed the presence of low-charged 2:1 clay minerals, the expansion of which was hindered in the untreated state by interlayered polymers. However, the hot citrate treatment encountered some problems with the samples of the south-facing soils: as confirmed by Fourier transform infrared spectroscopy, the hot citrate treatment was unable to remove all interlayer Al polymers. The 2:1 phyllosilicates were not expanded by ethylene glycol solvation in several samples, although thermogravimetric analyses indicated the presence of clay minerals with interlayer H2O. At the same time, the collapse of clay minerals to 1.0 nm following K-saturation was evident. Theoretically, this should indicate that 2:1 phyllosilicates had no evident substitution of trioctahedral cations (Mg2+, Fe2+) by dioctahedral cations (Al3+ and Fe3+). X-ray diffraction analysis of the d060 region and determination of the layer charge of clay minerals by the long-chain (C18) alkylammonium ion, however, did not confirm this. A transformation from trioctahedral to dioctahedral species was observed and low-charge clay minerals (ξ ~0.30) were identified in the surface horizons of the south-facing sites. In the south-facing soils, the podzolization process was less pronounced because of a lower water flux through the soil and probably less complexing organic molecules that would remove the interlayer polymers. Besides the eluviation process, clay minerals underwent a process of ionic substitutions in the octahedral sheet that led to the reduction of the layer charge. This process was more obvious in the north-facing sites.