GI,biliary tract and pancreas

Percutaneous stent-grafting is increasingly employed as a less invasive alternative to surgery for the treatment of infrarenal abdominal aortic aneurysms. It requires long-term imaging follow-up, to document the structural integrity of the device, to exculude perigraft channels and endograft leakages, as well as the shrinkage of the aneurysmal sac. The expectation of severe stent induced artifacts and safety concerns have prevented 3D MRA from being used. The purpose of this in vitro study was to investigate the imaging characteristics of a bifurcated stent graft with 3D MRA (3D Frourier transform fast spoiled GRE) at 1.5 T in comparison to those of CTA. Measurement of the stent wall thickness and luminal diameter were made on a agar gel embedded stent graft at five locations on both CTA and MRA images. The stent graft was depicted as a dark ring on MR images. Wall thickness measurments at the five locations of the stent graft overestimated the true stent thickness, while luminal diameters were slightly underestimated. Measurement differences between MR and CT were not statistically significant (P=0.67;P=0.85). Artifacts emanating from the platinum markers were considerably less severe on the MR-images. A wider area of signal loss was seen only at the insertion of the iliac stent leg into the aortic stent portion due to the overlap of two radio-opaque platinum markers. 3D MRA images should permit a comprehensive assessment of the arterial lumen, and of perivascular tissues.     

Are specific emotions narrated differently?

Two studies test the assertion that anger, sadness, fear, pride, and happiness are typically narrated in different ways. Everyday events eliciting these 5 emotions were narrated by young women (Study 1) and 5- and 8-year-old girls (Study 2). Negative narratives were expected to engender more effort to process the event, be longer, more grammatically complex, more often have a complication section, and use more specific emotion labels than global evaluations. Narratives of Hogan’s (2003) juncture emotions anger and fear were expected to focus more on action and to contain more core narrative sections of orientation, complication, and resolution than narratives of the outcome emotions sadness and happiness. Hypotheses were confirmed for adults except for syntactic complexity, whereas children showed only some of these differences. Hogan’s theory that juncture emotions are restricted to the complication section was not confirmed. Finally, in adults, indirect speech was more frequent in anger narratives and internal monologue in fear narratives. It is concluded that different emotions should be studied in how they are narrated, and that narratives should be analyzed according to qualitatively different emotions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Die Vorgehensweise des Bundesinstitutes für Risikobewertung bei der Abschätzung der dermalen Absorption von Wirkstoffen in Pflanzenschutzmitteln und Biozidprodukten

A correct estimate of dermal absorption of the contained active ingredients is needed for the health risk assessment of plant protection and biocidal products. In this paper, the approach is reported that is currently taken by the Federal Institute for Risk Assessment to derive the dermal absorption rate of active substances in plant protection or biocidal products, depending on the available data. It is explained what use is made of two new guidance documents that were recently released by EFSA and OECD. Basic principles of the assessment of dermal absorption studies are described but also opportunities for estimations in the absence of product-specific experimental data. This publication is considered a first step towards harmonisation of assessment in the authorisation processes for plant protection and biocidal products.     

Welche Bedeutung besitzt die Mehrfachverwendung von Nahrungsergänzungsmitteln? Daten einer deutschlandweiten Verbraucherbefragung

Today the use of dietary supplements in the form of vitamin and mineral preparations is partially widespread. Apart from their importance in relation to health, wellbeing and prevention the risk assessment of dietary supplements and a safe total nutrient intake play a crucial role. The supply of various products with same ingredients and the associated cumulative intakes of substances can be seen as a potential problem. Data on this were not yet available. The aim of this present analysis was to capture and further characterize the multiple use of dietary supplements in adult men and women. The data for this study was obtained from a representative survey in cooperation with the Society for Consumer, market and sales research (GfK) in Germany with 1.070 dietary supplement users. In 94 % of the cases, the supply of a specific nutrient came from a single preparation. With an increasing number of dietary supplements used, the mean vitamin and mineral intake increased as expected, at the same time, the number of supplement users dropped significantly. An exceedance of the Tolerable Upper Intake Level (UL) was of relevance mainly in view of magnesium. 68 % of the magnesium users exceeded the UL with the intake of a single product. Overall, the data obtained here indicated that vitamins and minerals were not taken multiple via different preparations. In this collective, multiple exposures via different dietary supplements harbored no exposed risk.     

Solar panel cooling system with hollow fibres

Photovoltaic (PV) panel overheating drastically reduces their efficiency and lifespan. Overheating also has the potential to form electric arcs which can melt metal fixtures and burn away the module’s insulating materials. Due to these phenomena, the introduction of water-cooling or, more generally, liquid-cooling systems inside the PV panel appears reasonable. Hollow fibre cooling system consisting of plastic tubes of a small diameter (less than 1 mm) was tested as a simple solution. Fibres can be placed in contact with the back surface of a PV panel and coolant flowing through provides efficient and uniform cooling. Heat removed from the panel may be used for domestic or industrial needs or released to the surroundings. Hollow fibres have very thin walls (about 0.1 mm) to transfer heat easily, and the system is light, compact and resistant to corrosion. Experiments confirmed that such system can cool the PV panel, removing up to 1 kW of heat and lowering the module temperature from 90°C to about 50°C. It was observed that cooling improves the electric efficiency of PV cells by about 50%.     

Modelling the effects of climate change on the energy system—A case study of Norway

The overall objective of this work is to identify the effects of climate change on the Norwegian energy system towards 2050. Changes in the future wind- and hydro-power resource potential, and changes in the heating and cooling demand are analysed to map the effects of climate change. The impact of climate change is evaluated with an energy system model, the MARKAL Norway model, to analyse the future cost optimal energy system. Ten climate experiments, based on five different global models and six emission scenarios, are used to cover the range of possible future climate scenarios and of these three experiments are used for detailed analyses. This study indicate that in Norway, climate change will reduce the heating demand, increase the cooling demand, have a limited impact on the wind power potential, and increase the hydro-power potential. The reduction of heating demand will be significantly higher than the increase of cooling demand, and thus the possible total direct consequence of climate change will be reduced energy system costs and lower electricity production costs. The investments in offshore wind and tidal power will be reduced and electric based vehicles will be profitable earlier.     

The inhibition by naphthoquinones and anthraquinones of 2-amino-3-methylimidazo[4,5-f ]quinoline metabolic activation to a mutagen: a structure-activity relationship study

 Nine naphthoquinones, 19 anthraquinones, and nine structurally related monoketonic compounds such as anthrone, xanthone, etc., inhibited mutagenicity induced by 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) in Salmonella typhimurium TA 98 in the presence of rat liver S9 with distinct structure-activity relationships. A carbonyl function was a prerequisite for antimutagenicity while, in general, anthraquinones (IC₅₀ values: 2.3–>213 nmol/ml top agar) were more potent antimutagens than structurally related monoketonic compounds (IC₅₀ values: 25.3–94.9 nmol/ml top agar) and naphthoquinones (IC₅₀ values: 3.7–90.7 nmol/ml top agar). The parent compounds and methyl substituted derivatives were already the most potent while introduction of polar substituents such as COOH and SO₃H considerably reduced antimutagenicity. Introduction of OH functions had equivocal effects: with increasing numbers, antimutagenic potencies were concomitantly reduced; however, anthraflavic acid, chrysazin, quinizarin, and especially 5,8-dihydroxy-1,4-naphthoquinone were more potent than the parent compounds. The patterns of inhibition by quinones of 7-ethoxyresorufin-O-dealkylase activities in rat liver microsomes, linked to cytochrome P-450-dependent oxidation of IQ to N-hydroxy-IQ (N-OH-IQ), were in general identical with those obtained in the Salmonella/reversion assay except for chrysophanic acid, emodin, and some naphthoquinones which were very potent in this assay (IC₅₀: 0.20–45.0 μM). On the other hand, mutagenicity of N-OH-IQ in S. typhimurium TA 98NR was not inhibited by nonpolar quinones (except 1,4-naphthoquinone) but rather by polar compounds and especially by hydroxyquinones (IC₅₀ values: 5.3–106.7 nmol/ml top agar or not reached). Inhibition of mutagenic activities of IQ, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline, 2-amino-6-methyldipyrido[1,2-a:3′,2′-d]imidazole, and 3-amino-1-methyl-5H-pyrido[4,3-b]indole by chrysazin, chrysophanic acid, physicon, and purpurin varied, but no clearcut structure-activity relationships of the mutagens were observed. Received: 29 May 1998