bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemical characteristics and fatty acid composition on oils and fats stored in different packaging materials
Authors: El-Shattory Y. , Saadia M. A. , Saeid F.
Published: May 2010

Bleached cottonseed oil, partially hydrogenated palm oil and margarine were stored in metal (tin) cans and white plastic (polyethylene) bottles with air in head space and served at room temperature during the whole period of investigation. The analytical techniques used to analyse these materials has been done at zero time storing (control), after four and seven months of storage. This study showed that storing oils in metal cans have better results than plastic packages specially for bleached cottonseed and hydrogenated oils.
Insecticides authorized for use on olive trees and the relationship between their registration and residues in olive oil
Authors: Lentza-Rizos Ch.
Published: May 2010

In order to eliminate losses due to insect attack, several insecticides are used on olive trees. Their residues in olive oil constitute an important parameter of its quality and must be monitored regularly and kept as low possible in order to ensure consumer protection. In this paper the insecticides authorized for use on olive trees are listed and their ADIs and Codex Alimentarius MRLs reported. The existing registrations are discussed from the point of view of their residues in oil.
Detergency. Its main mechanisms
Authors: Gómez Herrera Carlos
Published: May 2010

Advances on research, technology and applications for detergent processes increase rapidly. They keep provoking, as during last decades, repercussions on several fields (domestic, industrial, sanitary, energetic, environmental, legislative). To control as much as possible these repercussions, it is necessary to assess the actual knowledge about detergency mechanisms.
This informative article starts by reviewing the essential elements for detergent processes (substrate, soil, cleaning bath). Subsequently several physico-chemical key factors for effectiveness of the textile washing are discussed. These factors are: a) removal of liquid oily soils (by rolling-up, or by spontaneous microemulsification); b) separation of solid particles (by interfacial or electrostatic interactions); c) antiredeposition effects (by solubilization, emulsification or suspension); d) water hardness influence; e) washing physical conditions (temperature, agitation, time). The article ends by establishing the necessity for maintaining close collaboration among experts on different fields to optimize both detergent processes and their repercussions.
Dissolved inorganic and organic phosphorus uptake in Trichodesmium and the microbial community: The importance of phosphorus ester in the Sargasso Sea
Authors: Orchard Elizabeth D. , Ammerman James W. , Lomas Michael W. , Dyhrman Sonya T.
Published: May 2010

The dynamics and relative importance of inorganic phosphate (Pi) and dissolved organic phosphorus (DOP) uptake were examined in Trichodesmium and the microbial community. Trichodesmium DOP and Pi uptake rates were also compared to literature values from several other taxonomically important groups in the Sargasso Sea. Uptake rates and uptake kinetics of 33Pi and DOP (using alpha‐labeled adenosine‐5′‐triphosphate 33P‐ATP as a model P ester compound) were assayed during two cruises. The in situ uptake rates suggest that the contribution of P ester to total P uptake can be greater than 25% for Trichodesmium, the microbial community, and key phytoplankton groups (Prochlorococcus, Synechococcus, picoeukaryotes, and nanoeukaryotes), depending on the location. Based on the kinetics of Pi uptake and P ester uptake, Trichodesmium is a poor competitor for Pi but a much better competitor for P esters as compared to the microbial community. Trichodesmium growth rates calculated from the Pi and P ester uptake parameters suggest that only a small fraction of the P ester pool needs to be bioavailable to allow reasonable growth rates. These data underscore the importance of P esters in supporting production by Trichodesmium in the Sargasso Sea, and provide the first in situ measurements of P ester uptake and uptake kinetics in this important N2‐fixing genus.
Rapid photoprotection in sea‐ice diatoms from the East Antarctic pack ice
Authors: Petrou Katherina , Hill Ross , Brown Christopher M. , Campbell Douglas A. , Doblin Martina A. , Ralph Peter J.
Published: May 2010

Photoinhibition and D1 protein re‐synthesis were investigated in bottom‐dwelling sea‐ice microalgal communities from the East Antarctic pack ice during early spring. Bottom‐dwelling sea‐ice microalgal communities were dominated by diatoms that exhibited rapid photoprotection when exposed to a range of different light levels (10 µmol photons m−2 s−1, 50 µmol photons m−2 s−1, 100 µmol photons m−2 s−1, and 200 µ;mol photons m−2 s−1). Photosynthetic capacity of photosystem II (PSII) dropped significantly over 3 h under 200 −mol photons m−2 s−1, but largely recovered when placed in a low‐light environment (10 µmol photons m−2 s−1) for an additional 3 h. PSII repair rates increased with increasing irradiance, and the D1‐protein pool remained steady even under high light (200 µmol photons m−2 s−1). Sea‐ice diatoms showed a low intrinsic susceptibility to photoinactivation of PSII across all the light treatments, and a strong and irradiance‐dependent induction of nonphotochemical quenching, which did not depend upon chloroplast protein synthesis, was also seen. These highly plastic organisms, once thought to be adapted to shade, are in fact well equipped to withstand rapid and relatively large changes in light at low temperatures with minimal long‐term effect on their photosynthetic machinery.
Alkaline phosphatase activity and regulation in the North Pacific Subtropical Gyre
Authors: Duhamel Solange , Dyhrman Sonya T. , Karl David M.
Published: May 2010

Alkaline phosphatase (AP) activity (APA) was measured at several stations in the North Pacific Subtropical Gyre in July 2008, and in a series of nutrient addition experiments: nitrate plus ammonium (+N) or phosphate (+P), to study APA regulation and to evaluate the capacity of picoplankton organisms (i.e., in the 0.2–2‐µm size range) to access the AP‐hydrolyzable fraction of dissolved organic phosphorus (DOP). The data indicated a primary limitation of the biomass by nitrogen. Both total (measured with a soluble DOP analog) and cell‐specific (measured with the enzyme‐labeled fluorescence [ELF] phosphate cell labeling method) APA were enhanced in the +N samples and reduced in the +P samples, suggesting that DOP is an important resource for picoplankton nutrition. Cell‐free APA represented > 65% of the APA in all samples, but its contribution to total APA significantly decreased in the +N treatment as microbial biomass increased. In the +N treatment, < 5% and up to 96% of the cells in the heterotrophic bacteria‐enriched and picophytoplankton‐enriched fractions, espectively, were ELF‐alcohol‐labeled after 5 d. Following N enrichment, the microbial assemblage shifted from cell‐free phosphatase dominated under N limitation and P stress (i.e., physiological response) to picophytoplankton‐based phosphatase dominated under P limitation (i.e., production or growth rate limitation). If, as predicted, the ocean evolves towards P limitation, DOP availability would become of major importance to sustain productivity.
Interspecies differences in calcium content and requirement in four freshwater cladocerans explained by biokinetic parameters
Authors: Tan Qiao-Guo , Wang Wen-Xiong
Published: May 2010

We tested the hypothesis that cladocerans with higher calcium (Ca) content are more susceptible to Ca limitation by conducting life table experiments using four cladoceran species with contrasting Ca contents (0.06–2.24% of dry weight). Populations of Daphnia carinata and Daphnia galeata with high Ca content might collapse when the ambient Ca concentration is < 0.5 mg L−1, whereas Ceriodaphnia dubia, with intermediate Ca content, and Moina macrocopa, with low Ca content, are well adapted to that low Ca level. However, Ca content is not a good proxy of the susceptibilities to Ca limitation within the genus of Daphnia. We propose an index, which considers both the Ca demand (i.e., Ca content under Ca‐sufficient conditions) and the ability of cladocerans to extract and retain Ca in low‐Ca environments, to explain the differences in cladoceran tolerances to Ca deficiency. We also used physiologically based biokinetic parameters, including the influx rate and efflux rate constant of Ca, to predict the interspecies differences of specific Ca content. Low‐Ca species had a lower influx rate and a higher efflux rate constant of Ca than the high‐Ca species. A Ca concentration of 2 mg L−1 was sufficient to keep Daphnia spp. from extinction because of Ca limitation.
Relative importance of trophic interactions and nutrient enrichment in seagrass ecosystems: A broad‐scale field experiment in the Baltic−Skagerrak area
Authors: Baden Susanne , Boström Christoffer , Tobiasson Stefan , Arponen Heidi , Moksnes Per-Olav
Published: May 2010

The interaction of eutrophication and predation in structuring seagrass Zostera marina L. ecosystems was assessed in a field experiment in three regions along an estuarine salinity gradient, from southern Finland to the Skagerrak area of the Swedish west coast. All regions are considered to be affected by eutrophication and overfishing but differ in the abundance of intermediate predators (e.g., small fish, shrimp, and crabs), mesograzers, and the biomass of epiphytic algae. Using transplanted Zostera (eelgrass), nutrient levels and intermediate predator abundance were manipulated in a full‐factorial cage experiment. On the Swedish west coast, where ambient densities of mesograzers are very low, epiphytic algae responded strongly to nutrient enrichment, resulting in significantly reduced growth of eelgrass. At the Baltic sites however, where ambient densities of mesograzers are high, no significant growth of epiphytic algae was detected, and only grazer biomass responded to nutrient enrichment. Predation from small fish, shrimp, and crabs decreased the biomass of mesograzers by > 98% on the Swedish west coast, but natural predators had no significant effect on mesograzers biomass at the Baltic sites. Predation and nutrient enrichment interacted to affect the growth of eelgrass by controlling the biomass of mesograzers and nuisance algae. The differing effect of nutrient enrichment and grazing in the three regions may therefore be a result of the prevailing low and high predation pressure on mesograzers in Zostera. This absence or presence of predation may derive from interregional changes in trophic interactions, possibly caused by a combination of eutrophication and overfishing.
Illuminated darkness: Molecular signatures of Congo River dissolved organic matter and its photochemical alteration as revealed by ultrahigh precision mass spectrometry
Authors: Stubbins Aron , Spencer Robert G. M. , Chen Hongmei , Hatcher Patrick G. , Mopper Kenneth , Hernes Peter J. , Mwamba Vincent L. , Mangangu Arthur M. , Wabakanghanzi Jose N. , Six Johan
Published: May 2010

Congo River water was filtered and then irradiated for 57 d in a solar simulator, resulting in extensive photodegradation of dissolved organic matter (DOM). Whole‐water (i.e., unfractionated) DOM was analyzed pre‐ and post‐irradiation using ultrahigh resolution Fourier transform ion cyclotron mass spectrometry (FT‐ICR MS), revealing the following three pools of DOM classified based upon their photoreactivity: (1) photo‐resistant, (2) photo‐labile, and (3) photo‐produced. Photo‐resistant DOM was heterogeneous, with most molecular classes represented, although only a small number of aromatics and no condensed aromatics were identified. The photoproduced pool was dominated by aliphatic compounds, although it included a small number of aromatics, including condensed aromatics. Aromatic compounds were the most photoreactive, with > 90% being lost upon irradiation. Photochemistry also resulted in a significant drop in the number of molecules identified and a decrease in their structural diversity. The FT‐ICR MS signatures of two classes of refractory organic matter, black carbon and carboxylic‐rich alicyclic molecules (CRAM), were present in the sample prior to irradiation, indicating that the Congo River could be a significant exporter of recalcitrant DOM to the ocean. All black carbon‐like molecules identified in the initial sample were lost during irradiation. Molecular signatures consistent with CRAM were also highly photo‐labile, demonstrating that environmental solar irradiation levels are capable of removing these refractory compounds from aquatic systems. Irradiation also shifted the molecular signature of terrestrial DOM toward that of marine DOM, thereby complicating the task of tracking terrestrial DOM in the ocean.
Building Local Communities: Place-Shaping as Nation-Building
Authors: Van de Walle Steven
Published: May 2010

The Lyons Inquiry into Local Government has introduced the English local government community to the concept of ‘place-shaping’. Place-shaping refers to the new role for local governments in promoting the well-being of communities and citizens. The processes of place-shaping are remarkably similar to the processes of nation-building. This paper uses Stein Rokkan’s thinking on nation-building in Western Europe to analyse place-shaping. It focuses on the penetration and standardisation processes and underlines the importance of integrating peripheries, defining boundaries, and creating identities. In essence, it is argued that place-shaping is really about the repolitisation of English local authorities.
Indigenous Peoples: From Unrighteousness to the Right to Self-Government
Authors: Kraljić Suzana , Stolz Armin-Bernhard
Published: May 2010

In the past, indigenous peoples were exposed to many violations of human rights. They were treated as nations without rights and civilisation. Colonial powers confiscated their land without paying any compensation. Their culture, religion, language, social and judicial systems were annulled or even destroyed. Members of indigenous peoples were victims of ethnocide/genocide and were used as cheap labour force. Today, many live on the edge of human society and deal with different problems (alcohol, drugs, crime). National efforts and trends to abolish the injustice made in the past, and efforts for the improvement of the present situation of members of indigenous peoples have brought fruit because indigenous peoples have reached a certain degree of autonomy in different countries through the right to self-determination and the right to self-government. Declaration on the Rights of Indigenous Peoples was adopted in 2007. It represents an important milestone in resolving many issues associated with indigenous peoples, even though individual countries with many indigenous peoples have not supported it.
Reconsidering Rationales for Local Self-Government - Impacts of Contemporary Changes in Local Decision-Making
Authors: Lyngstad Rolv
Published: May 2010

This paper discusses two contemporary trends in local decision-making. Firstly, there seems to be more centralised decision-making today than before in important policy fields such as welfare policy. Secondly, informal governance processes outside formal government structures open up for a substantial influence from non-elected political actors. The paper asserts that there is a connection between the trends, and argues that the centralisation tendencies in welfare issues might affect and encourage governance processes in other local policy arenas. These policy fields are mainly within the so-called ‘developmental policies’ that often facilitate more networking and partnership activities in ‘grey areas’ between the public, private and civil sectors in collective problem solving. Accordingly, more attention should be given to policy fields where governance networks operate, and the implications for revitalising democratic political participation should be studied. The paper concludes that the well-established rationales for local self-government and local democracy need to be reconsidered by taking into account these new decision-making structures.
Impacts of transported background ozone on California air quality during the ARCTAS-CARB period – a multi-scale modeling study
Authors: Huang M. , Carmichael G. R. , Adhikary B. , Spak S. N. , Kulkarni S. , Cheng Y. , Wei C. , Tang Y. , Parrish D. D. , Oltmans S. J. , D'Allura A. , Kaduwela A. , Cai C. , Weinheimer A. J. , Wong M. , Pierce R. B. , Al-Saadi J. A. , Streets D. G. , Zhang Q.
Published: May 2010

Abstract. Multi-scale tracer and full-chemistry simulations with the STEM atmospheric chemistry model are used to analyze the effects of transported background ozone (O3) from the eastern Pacific on California air quality during the ARCTAS-CARB experiment conducted in June 2008. Previous work has focused on the importance of long-range transport of O3 to North America air quality in springtime. However during this summer experiment the long-range transport of O3 is also shown to be important. Simulated and observed O3 transport patterns from the coast to inland northern California are shown to vary based on meteorological conditions and the oceanic O3 profiles, which are strongly episodically affected by Asian inflows. Analysis of the correlations of O3 at various altitudes above the coastal site at Trinidad Head and at a downwind surface site in northern California, show that under long-range transport events, high O3 air-masses (O3>60 ppb) at altitudes between about 2 and 4 km can be transported inland and can significantly influence surface O3 20–30 h later. These results show the importance of characterizing the vertical structure of the lateral boundary conditions (LBC) needed in air quality simulations. The importance of the LBC on O3 prediction during this period is further studied through a series of sensitivity studies using different forms of LBC. It is shown that the use of the LBC downscaled from RAQMS global model that assimilated MLS and OMI data improves the model performance. We also show that the predictions can be further improved through the use of LBC based on NASA DC-8 airborne observations during the ARCTAS-CARB experiment. These results indicate the need to develop observational strategies to improve the representation of the vertical and temporal variations in the air over the eastern Pacific.
Long-term trends of black carbon and sulphate aerosol in the Arctic: changes in atmospheric transport and source region emissions
Authors: Hirdman D. , Burkhart J. F. , Sodemann H. , Eckhardt S. , Jefferson A. , Quinn P. K. , Sharma S. , Ström J. , Stohl A.
Published: May 2010

Abstract. As a part of the IPY project POLARCAT (Polar Study using Aircraft, Remote Sensing, Surface Measurements and Models, of Climate, Chemistry, Aerosols and Transport) and building on previous work (Hirdman et al., 2010), this paper studies the long-term trends of both atmospheric transport as well as equivalent black carbon (EBC) and sulphate for the three Arctic stations Alert, Barrow and Zeppelin. We find a general downward trend in the measured EBC concentrations at all three stations, with a decrease of −2.1±0.4 ng m−3 yr−1 (for the years 1989–2008) and −1.4±0.8 ng m−3 yr−1 (2002–2009) at Alert and Zeppelin respectively. The decrease at Barrow is, however, not statistically significant. The measured sulphate concentrations show a decreasing trend at Alert and Zeppelin of −15±3 ng m−3 yr−1 (1985–2006) and −1.3±1.2 ng m−3 yr−1 (1990–2008) respectively, while the trend at Barrow is unclear. To reveal the influence of different source regions on these trends, we used a cluster analysis of the output of the Lagrangian particle dispersion model FLEXPART run backward in time from the measurement stations. We have investigated to what extent variations in the atmospheric circulation, expressed as variations in the frequencies of the transport from four source regions with different emission rates, can explain the long-term trends in EBC and sulphate measured at these stations. We find that the long-term trend in the atmospheric circulation can only explain a minor fraction of the overall downward trend seen in the measurements of EBC (0.3–7.2%) and sulphate (0.3–5.3%) at the Arctic stations. The changes in emissions are dominant in explaining the trends. We find that the highest EBC and sulphate concentrations are associated with transport from Northern Eurasia and decreasing emissions in this region drive the downward trends. Northern Eurasia (cluster: NE, WNE and ENE) is the dominant emission source at all Arctic stations for both EBC and sulphate during most seasons. In wintertime, there are indications that the EBC emissions from the eastern parts of Northern Eurasia (ENE cluster) have increased over the last decade.
Assessing modelled spatial distributions of ice water path using satellite data
Authors: Eliasson S. , Buehler S. A. , Milz M. , Eriksson P. , John V. O.
Published: May 2010

Abstract. The climate models used in the IPCC AR4 show large differences in monthly mean cloud ice. The most valuable source of information that can be used to potentially constrain the models is global satellite data. For this, the data sets must be long enough to capture the inter-annual variability of Ice Water Path (IWP). PATMOS-x was used together with ISCCP for the annual cycle evaluation in Fig. 7 while ECHAM-5 was used for the correlation with other models in Table 3. A clear distinction between ice categories in satellite retrievals, as desired from a model point of view, is currently impossible. However, long-term satellite data sets may still be used to indicate the climatology of IWP spatial distribution. We evaluated satellite data sets from CloudSat, PATMOS-x, ISCCP, MODIS and MSPPS in terms of monthly mean IWP, to determine which data sets can be used to evaluate the climate models. IWP data from CloudSat cloud profiling radar provides the most advanced data set on clouds. As CloudSat data are too short to evaluate the model data directly, it was mainly used here to evaluate IWP from the other satellite data sets. ISCCP and MSPPS were shown to have comparatively low IWP values. ISCCP shows particularly low values in the tropics, while MSPPS has particularly low values outside the tropics. MODIS and PATMOS-x were in closest agreement with CloudSat in terms of magnitude and spatial distribution, with MODIS being the best of the two. As PATMOS-x extends over more than 25 years and is in fairly close agreement with CloudSat, it was chosen as the reference data set for the model evaluation. In general there are large discrepancies between the individual climate models, and all of the models show problems in reproducing the observed spatial distribution of cloud-ice. Comparisons consistently showed that ECHAM-5 is the GCM from IPCC AR4 closest to satellite observations.
Aerosol nucleation and its role for clouds and Earth's radiative forcing in the aerosol-climate model ECHAM5-HAM
Authors: Kazil J. , Stier P. , Zhang K. , Quaas J. , Kinne S. , O'Donnell D. , Rast S. , Esch M. , Ferrachat S. , Lohmann U. , Feichter J.
Published: May 2010

Abstract. Nucleation from the gas phase is an important source of aerosol particles in the Earth's atmosphere, contributing to the number of cloud condensation nuclei, which form cloud droplets. We have implemented in the aerosol-climate model ECHAM5-HAM a new scheme for neutral and charged nucleation of sulfuric acid and water based on laboratory data, and nucleation of an organic compound and sulfuric acid using a parametrization of cluster activation based on field measurements. We give details of the implementation, compare results with observations, and investigate the role of the individual aerosol nucleation mechanisms for clouds and the Earth's radiative budget. The results of our simulations are most consistent with observations when neutral and charged nucleation of sulfuric acid proceed throughout the troposphere and nucleation due to cluster activation is limited to the forested boundary layer. The globally averaged annual mean contributions of the individual nucleation processes to total absorbed solar short-wave radiation via the direct, semi-direct, indirect cloud-albedo and cloud-lifetime effects in our simulations are −1.15 W/m2 for charged H2SO4/H2O nucleation, −0.235 W/m2 for cluster activation, and −0.05 W/m2 for neutral H2SO4/H2O nucleation. The overall effect of nucleation is −2.55 W/m2, which exceeds the sum of the individual terms due to feedbacks and interactions in the model. Aerosol nucleation contributes over the oceans with −2.18 W/m2 to total absorbed solar short-wave radiation, compared to −0.37 W/m2 over land. We explain the higher effect of aerosol nucleation on Earth's radiative budget over the oceans with the larger area covered by ocean clouds, due to the larger contrast in albedo between clouds and the ocean surface compared to continents, and the larger susceptibility of pristine clouds owing to the saturation of effects. The large effect of charged nucleation in our simulations is not in contradiction with small effects seen in local measurements: over southern Finland, where cluster activation proceeds efficiently, we find that charged nucleation of sulfuric acid and water contributes on average less than 10% to ultrafine aerosol concentrations, in good agreement with observations.
Heterogeneous reactions of carbonyl sulfide on mineral oxides: mechanism and kinetics study
Authors: Liu Y. , Ma J. , He H.
Published: May 2010

Abstract. The heterogeneous reactions of carbonyl sulfide (OCS) on the typical mineral oxides in the mineral dust particles were investigated using a Knudsen cell flow reactor and an in situ diffuse reflectance UV-vis spectroscopy. The reaction pathway for OCS on mineral dust was identified based on the gaseous products and surface species. The hydrolysis of OCS, and succeeding oxidation of intermediate products, readily take place on α-Al2O3, MgO, and CaO. The reversible and irreversible adsorption of OCS on α-Fe2O3 and ZnO were observed, respectively. No uptake of OCS by SiO2 and TiO2 was observed. The uptake coefficient (γBET) of mineral dust was estimated to be from 3.84×10−7 to 2.86×10−8 based on the individual uptake coefficients and chemical composition of authentic mineral dust. The global flux of OCS due to heterogeneous reactions and adsorption on mineral dust was estimated at 0.13–0.29 Tg yr−1, which is comparable to the annual flux of OCS for its reaction with ·OH.
The relevance of glacier melt in the water cycle of the Alps: an example from Austria
Authors: Koboltschnig G. R. , Schöner W.
Published: May 2010

Abstract. This paper gives an overview on available methods how the contribution of glacier melt to runoff can be calculated with and without glaico-hydrological models. Further we applied an approach, which shows the potential of glacier melt contribution during the extreme hot and dry summer of 2003 by calculating the quotient qA03 of the mean monthly August runoff in 2003 and the long-term mean August runoff. The extreme summer 2003 was worth to be analysed as from the meteorological and glaciological point of view an extraordinary situation was observed. During June and July nearly the entire snow-cover melted and during the hot and dry August mainly ice melt of glaciers contributed to runoff. The mean runoff in August 2003 was calculated from observed mean daily runoff data of a selected period in August 2003 (3 to 27 August). This was done for 27 Austrian gauging stations in the glacierized basins of the rivers Inn, Salzach and Drau with a degree of glaciation between 2 and 76%. The quotient qA03 was calculated between 0.63 and 1.82, which means for the lower value that only 63% of the long-term mean August runoff and for the higher value 82% more than the long-term mean August runoff was observed in 2003. Additionally two stations at river Danube (0.4 and 1% glacierized) and further six gauging stations in catchments with no glacier cover were investigated to define qA03 quotients for non-glacierized basins. These qA03 quotients were calculated between 0.31 and 0.54. Hence, it was possible to qualitatively visualize the decreasing impact of glacier melt for a decreasing degree of glaciation. Nevertheless, for the accurate calculation of the glacier melt contribution for a certain catchment scale and time a glaio-hydrological model is needed.
Rheological investigation and simulation of a debris-flow event in the Fella watershed
Authors: Boniello M. A. , Calligaris C. , Lapasin R. , Zini L.
Published: May 2010

Abstract. To set an approach for the future territorial planning, the Geological Survey of Friuli Venezia Giulia Region, through the researchers of Trieste University, started a program of debris-flow risk analysis using Flo-2D software as tool to delimit the hazardous areas. In the present paper, as a case study, a debris flow, called Fella sx, occurring in a torrent catchment was analyzed. The choice was due to the abundance of information about past events, inundated areas, rain fall, geology and to its representativeness. An initial back-analysis investigation identified a couple of representative rheological parameters. Riverbed samples were collected, sieve analyses were performed and rheological tests were carried out on the fraction finer than 0.063 mm using a rotationally controlled stress rehometer equipped with the serrated parallel plate geometry. The shear dependent behaviour was examined at different concentrations ranging from 33 to 48%, by weight. Viscosity data treatment was performed to determine the most suitable rheological model to provide the best approximation of the debris-flow behaviour. The rheological parameters, derived from experimental data, were used and compared with those obtained through the back-analysis and with the real inundated area. Data obtained through rheological analysis are useful in constructing scenarios of future events where no data for back-analysis are available.
Modelling snowdrift sublimation on an Antarctic ice shelf
Authors: Lenaerts J. T. M. , van den Broeke M. R. , Déry S. J. , König-Langlo G. , Ettema J. , Munneke P. K.
Published: May 2010

Abstract. In this paper, we estimate the contribution of snowdrift sublimation (SUds) to the surface mass balance at Neumayer, located on the Ekström ice shelf in Eastern Antarctica. A single column version of the RACMO2-ANT model is used as a physical interpolation tool of high-quality radiosonde and surface measurements for a 15-yr period (1993–2007), and combined with a routine to calculate snowdrift sublimation and horizontal snow transport. The site is characterised by a relatively mild, wet and windy climate, so snowdrift is a common phenomenon. The modelled timing and frequency of snowdrift events compares well with observations. This is further illustrated by an additional simulation for Kohnen base, where the timing of snowdrift is realistic, although the modelled horizontal transport is overestimated. Snowdrift sublimation is mainly dependent on wind speed, but also on relative humidity and temperature. During high wind speeds, SUds saturates and cools the air, limiting its own strength. We estimate that SUds removes around 16%±8% of the accumulated snow from the surface. The total sublimation more than triples when snowdrift is considered, although snowdrift sublimation limits sublimation at the surface. SUds shows a strong seasonal cycle, as well as large inter-annual variability. This variability can be related to the variability of the atmospheric conditions in the surface layer.
Hybridkatalysatoren auf DNA‐Basis für die asymmetrische organische Synthese
Authors: Park Soyoung , Sugiyama Hiroshi
Published: May 2010

Stereoselektive Hybridsysteme auf der Grundlage von Metallkatalysatoren und einem chiralen Biomakromolekül stellen hinsichtlich der Synthese enantiomerenreiner Verbindungen ein aussichtsreiches Forschungsfeld dar. Obschon für diesen Zweck verschiedene Methoden zur Verfügung stehen, stützen sich die meisten auf den Einsatz von Enzymen, anderen Proteinen oder RNA. Die Anwendung DNA‐haltiger Hybridkatalysatoren in der enantioselektiven Synthese trat erst vor wenigen Jahren hinzu. Solche Hybridkatalysatoren sind durch Selbstorganisation von DNA und einem Metallkomplex mit einem spezifischen Liganden mithilfe von supramolekularen oder kovalenten Verankerungsstrategien hergestellt worden und haben bei Lewis‐Säure‐katalysierten Diels‐Alder‐, Michael‐ oder Friedel‐Crafts‐Reaktionen hohe Stereoselektivitäten und Geschwindigkeitserhöhungen ergeben. Dabei kam im Allgemeinen käufliche DNA aus Lachssperma zum Einsatz. Hier fassen wir aktuelle Fortschritte auf dem Gebiet der asymmetrischen Katalyse mit Hybridkatalysatoren auf DNA‐Basis zusammen.
DNA‐Based Hybrid Catalysts for Asymmetric Organic Synthesis
Authors: Park Soyoung , Sugiyama Hiroshi
Published: May 2010

Stereoselective hybrid systems based on metal‐assisted catalysis with a chiral biomacromolecule form an attractive research area for the synthesis of enantiomerically pure compounds. Although various methods are available for this purpose, most rely on the use of enzymes, proteins, or RNA. The application of DNA‐based hybrid catalysts for enantioselective synthesis emerged only a few years ago. DNA‐based hybrid catalysts have been self‐assembled from DNA and a metal complex with a specific ligand through supramolecular or covalent anchoring strategies and have demonstrated high stereoselectivity and rate enhancement in Lewis acid catalyzed reactions, such as Diels–Alder, Michael addition, and Friedel–Crafts reactions. For these reactions, cheap and commercially available salmon testes DNA has generally been used. In this Minireview, we summarize recent developments in the area of asymmetric catalysis with DNA‐based hybrid catalysts.
Synthesis of 1,2,3,4,8,9,10,11‐Octasubstituted Pentacenequinone Derivatives and their Conversion into Substituted Pentacenes
Authors: Li Shi , Zhou Lishan , Nakajima Kiyohiko , Kanno Ken‐ichiro , Takahashi Tamotsu
Published: May 2010

A series of 1,2,3,4,8,9,10,11‐octasubstituted pentacenequinone derivatives were prepared by the oxidation of 1,2,3,4,8,9,10,11‐octasubstituted pentacenes, which were synthesized by the double homologation method. Oxidation of the pentacenes was carried out with H5IO6 or air and DDQ. These octasubstituted pentacenequinones were converted into 1,2,3,4,6,8,9,10,11,13‐decasubstituted or 2,3,6,9,10,13‐hexasubstituted pentacene derivatives by the introduction of aryl or alkynyl groups at the carbonyl carbons. The photophysical properties of these new pentacenes have been measured in solution, and the substituent effects are discussed.
Auf der Suche nach der Politik in der Wissensproduktion: Plädoyer für eine historisch‐politische Epistemologie
Authors: Roelcke Volker
Published: May 2010

In Search of Politics in Knowledge Production. A Plea for a Historical‐Political Epistemology. Knowledge production has an intrinsic political dimension. Starting from this presupposition, it is argued that the systematic integration of and reflection on the political dimension is necessary for an adequate understanding of historical processes of knowledge production in the sciences. The consecutive plea for a historical‐political epistemology proceeds in two steps: First, it is illustrated that in a number of recent historical science study cases, the political dimension is frequently marginal, or even absent. After a short discussion of previous theoretical concepts to describe the impact of politics for the production of scientific knowledge, an approach is sketched which builds on Hans‐Jörg Rheinberger's historical epistemology and Bruno Latour's symmetrical anthropology. It is argued that in addition to Rheinberger's program to describe epistemic systems, the political dimension is intrinsic to three stages of the process of data production: First to an initial phase which consists in the arrangement socio‐technical configurations to produce new evidence. Here, factors such as the culturally shaped perception and evaluation of „relevant”︁ problems, as well as the perception of career resources have to be taken into account. Second, the political dimension is relevant in view of the continuous re‐adjustments of the configuration of epistemic systems, e. g. towards newly available financial, technical, or intellectual resources and „relevant”︁ challenges from outside the system. Thirdly, the data produced and represented by epistemic systems – “evidence” – are yet in need of interpretation. This process is in itself imbued with continuously shifting mechanisms of selecting and creating hierarchies amongst the pool of available data.
Über Georges Canguilhems Was heißt eine wissenschaftliche Ideologie? und über deutsch‐französische Beiträge zum Thema Wissenschaft und Ideologie aus den letzten vierzig Jahren
Authors: Debru Claude
Published: May 2010

On Georges Canguilhem's What does a Scientific Ideology mean? and on French‐German Contributions on Science and Ideology in the Last Fourty Years. This paper is based on Canguilhem's text on the concept of scientific ideology, which he introduced in 1969. We describe Canguilhem's attempts at designing a methodological framework for the history of science including the status of kinds of knowledge related to science, like scientific ideologies preceding particular scientific domains (like ideologies about inheritance before Mendel, or Spencer's universal evolutionary laws preceding Darwin). This attempt at picturing the relationships between science and ideology is compared with Jürgen Habermas's book Technology and Science as ‘Ideology’ in 1968. The philosphical issue of human normativity provides the framework of this discussion.
A fully defined, fed‐batch, recombinant NS0 culture process for monoclonal antibody production
Authors: Hermes Paul A. , Castro Chris D.
Published: May 2010

To manufacture a glycoprotein, mammalian cells expressing the desired protein are often grown in fed‐batch mode. Feeding an undefined, nonanimal hydrolysate helps the cells receive sufficient nutrition, but makes systems difficult to optimize. Even different lots of the same hydrolysate may have significant variability; furthermore, individual components may actually be detrimental to the cells. Switching to fully defined feeds could eliminate these issues. For monoclonal antibody (mAb) production by fed‐batch NS0 cells, this article describes the replacement of a hydrolysate‐based feed with a fully defined, animal‐component‐free feed system. The defined feed initially had 67 components, but additional experiments allowed a reduction to 25 components. The mAb titer is approximately 20% higher than in the undefined system, and the feed volume is circa 20% lower. The two systems generated antibodies with similar glycosylation profiles. Other benefits of the defined feed system include lower raw material costs, the ability to optimize key nutrient concentrations, greater confidence in raw material quality, and the elimination of potential, hydrolysate‐associated endotoxin issues. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010
Selective Binding of Imidazolium Cations in Building Multi‐Component Layers
Authors: Ling Irene , Alias Yatimah , Sobolev Alexandre N. , Byrne Lindsay T. , Raston Colin L.
Published: May 2010

Addition of 1‐alkyl‐3‐methylimidazolium (Cn‐mim) cations 3–5 to a mixture of bis‐phosphonium cation 2 and sodium p‐sulfonatocalix[4]arene (1) in the presence of lanthanide ions results in the selective binding of an imidazolium cation into the cavity of the calixarene. The result is a multi‐layered solid material with an inherently flexible interplay of the components. Incorporating ethyl‐, n‐butyl‐ or n‐hexyl‐mim cations into the multi‐layers results in significant perturbation of the structure, the most striking effect is the tilting of the plane of the bowl‐shaped calixarene relative to the plane of the multi‐layer, with tilt angles of 7.2, 28.9 and 65.5°, respectively. The lanthanide ions facilitate complexation, but are not incorporated into the structures and, in all cases, the calixarene takes on a 5− charge, with one of the lower‐rim phenolic groups deprotonated. ROESY NMR experiments and other 1H NMR spectroscopy studies establish the formation of 1:1 supermolecules of Cn‐mim and calixarene, regardless of the ratio of the two components, and indicate that the supermolecules undergo rapid exchange on the NMR spectroscopy timescale.
Rapid and Selective Catalytic Oxidation of Secondary Alcohols at Room Temperature by Using (N‐Heterocyclic Carbene)–Ni0 Systems
Authors: Berini Christophe , Winkelmann Ole H. , Otten Jennifer , Vicic David A. , Navarro Oscar
Published: May 2010

The selective, anaerobic catalytic oxidation of secondary alcohols at room temperature by using an in situ (N‐heterocyclic carbene)–Ni0 system is presented. The use of non‐anhydrous, non‐degassed 2,4‐dichlorotoluene as both the oxidant and the solvent allows for very short reaction times and very high yields. In addition, a well‐defined (N‐heterocyclic carbene)–Ni0 complex was synthesized and applied to these oxidation reactions.
An Internal Fluorescent Probe Based on Anthracene to Evaluate Cation–Anion Interactions in Imidazolium Salts
Authors: Fei Zhaofu , Zhu Dun‐Ru , Yang Xue , Meng Lingjie , Lu Qinghua , Ang Wee Han , Scopelliti Rosario , Hartinger Christian G. , Dyson Paul J.
Published: May 2010

A series of fluorescent imidazolium‐based salts containing the cation [AnCH2MeIm]+ (in which An=anthracene and Im=the imidazolium cation) with Cl−, BF4−, PF6−, SO3CF3−, [N(CN)2]−, [N(SO2CF3)2]−, or PhBF3− anions have been prepared and characterized. X‐ray diffraction analysis of four of the salts reveals a number of CH⋅⋅⋅X‐type (X=O, N, F) hydrogen bonds between the hydrogen atoms from the imidazolium ring and in some cases from the anthracene ring with the electronegative atoms of the anions. Additionally, CH⋅⋅⋅π interactions can be found in all the salts analyzed by X‐ray diffraction, whereas π–π stacking is observed only in the salt containing the phenyltrifluoroborate anion. Fluorescence emission analysis in acetonitrile shows that the fluorescence of these salts varies significantly according to the nature of the anion, and correlates to the extent of ion pairing present in solution. Photodimerization of these salts was observed, and in one case a dimer has been isolated and characterized by X‐ray crystallography.
Mild, Single‐Pot Hydrocarboxylation of Gaseous Alkanes to Carboxylic Acids in Metal‐Free and Copper‐Promoted Aqueous Systems
Authors: Kirillova Marina V. , Kirillov Alexander M. , Pombeiro Armando J. L.
Published: May 2010

A direct, selective and highly efficient method has been developed for the hydrocarboxylation of Cn gaseous alkanes into Cn+1 carboxylic acids, in aqueous acid‐solvent‐free medium at low temperatures. The approach is based on a metal‐free or copper‐promoted reaction of ethane, propane or n‐butane with carbon monoxide and water, in a H2O/MeCN medium at 50–60 °C, in the presence of potassium peroxodisulfate. The effects of various reaction parameters, such as the absence or presence of a copper promoter, solvent composition, temperature, time, CO and alkane pressure, were studied. A free radical mechanism was confirmed by radical trap experiments involving acyl radical formation, oxidation and subsequent hydroxylation by water. Remarkable yields (based on alkane) of carboxylic acids in the 34–41 % range were achieved even in the metal‐free systems, although in the presence of a tetracopper(II) triethanolaminate derived promoter they reach superior values of 58 and 87 % for the hydrocarboxylations of propane and n‐butane, respectively; in these cases, branched isobutyric and 2‐methylbutyric acids were the predominant products. From a green perspective, important features of the present alkane hydrocarboxylations include the exceptional metal‐free, mild and acid‐solvent‐free reaction conditions, the operation in aqueous medium with a rare hydroxylating role of water, with high selectivities, and yields of carboxylic acids. Taken together, these conditions correspond to the mildest and the most efficient method so far reported for the oxidative functionalisation of gaseous alkanes.
HIV‐1 impairs in vitro priming of naïve T cells and gives rise to contact‐dependent suppressor T cells
Authors: Che Karlhans F. , Sabado Rachel L. , Shankar Esaki M. , Tjomsland Veronica , Messmer Davorka , Bhardwaj Nina , Lifson Jeffrey D. , Larsson Marie
Published: May 2010

Priming of T cells in lymphoid tissues of HIV‐infected individuals occurs in the presence of HIV‐1. DC in this milieu activate T cells and disseminate HIV‐1 to newly activated T cells, the outcome of which may have serious implications in the development of optimal antiviral responses. We investigated the effects of HIV‐1 on DC–naïve T‐cell interactions using an allogeneic in vitro system. Our data demonstrate a dramatic decrease in the primary expansion of naïve T cells when cultured with HIV‐1‐exposed DC. CD4+ and CD8+ T cells showed enhanced expression of PD‐1 and TRAIL, whereas CTLA‐4 expression was observed on CD4+ T cells. It is worth noting that T cells primed in the presence of HIV‐1 suppressed priming of other naïve T cells in a contact‐dependent manner. We identified PD‐1, CTLA‐4, and TRAIL pathways as responsible for this suppresion, as blocking these negative molecules restored T‐cell proliferation to a higher degree. In conclusion, the presence of HIV‐1 during DC priming produced cells with inhibitory effects on T‐cell activation and proliferation, i.e. suppressor T cells, a mechanism that could contribute to the enhancement of HIV‐1 pathogenesis.
A Supramolecular Derivative of a Nanoporous Molybdenum Oxide Based Inorganic Keplerate with Self‐Defocusing Nonlinear Optical Properties
Authors: Zhang Lijuan , Zhou Yunshan , Han Ruixue
Published: May 2010

A new derivative of the highly charged inorganic Keplerate of the type {pentagon}12{linker}30 ≡ {(Mo)Mo5O21(H2O)6}12{Mo2O4(SO4)}30 with the formula (NH4)28(NH2CHNH2)6Gd3[{(NH2CHNH2)20 + Gd3 + (H2O)50} ⊂ {(MoVI)MoVI5O21(H2O)6}12 {MoV2O4(SO4)}30]·ca.250H2O was isolated and characterized by elemental analysis, IR and UV/Vis spectroscopy, single‐crystal X‐ray analysis, and magnetic susceptibility measurements. Three Gd3+ ions are found inside the internal cavity of the capsule. The coordination sphere of each Gd3+ ion is completed by the oxygen atoms of SO4 groups that act as bidentate ligands to a {Mo2} linker and by the oxygen atoms of the encapsulated new two‐shell underoccupied [{H2O}60+20 + {H2O}20] water cluster that acts as polydentate ligand. Twenty HC(NH2)2+ cations interact with the twenty {Mo9O9} pores through hydrogen bonds between the O and H atoms of the two NH2 groups, which demonstrates a surface supramolecular chemistry. Of importance, a third‐order nonlinear optical investigation, using the Z‐scan technique, shows for the first time that the derivative demonstrates a strong self‐defocusing third‐order nonlinear optical effect with large third‐order nonlinear optical susceptibility. This observation implies that these unique inorganic Keplerates and their derivatives might find applications in nonlinear optical materials science.