Acute Cardiovascular Effects of Controlled Exposure to Dilute Petrodiesel and Biodiesel Exhaust in Healthy Volunteers: A Crossover Study

Abstract Background Air pollution derived from combustion is associated with considerable cardiorespiratory morbidity and mortality in addition to environmental effects. Replacing petrodiesel with biodiesel may have ecological benefits, but impacts on human health remain unquantified. The objective was to compare acute cardiovascular effects of blended and pure biodiesel exhaust exposure against known adverse effects of petrodiesel exhaust (PDE) exposure in human subjects. In two randomized controlled double-blind crossover studies, healthy volunteers were exposed to PDE or biodiesel exhaust for one hour. In study one, 16 subjects were exposed, on separate occasions, to PDE and 30% rapeseed methyl ester biodiesel blend (RME30) exhaust, aiming at PM10 300 μg/m3. In study two, 19 male subjects were separately exposed to PDE and exhaust from a 100% RME fuel (RME100) using similar engine load and exhaust dilution. Generated exhaust was analyzed for physicochemical composition and oxidative potential. Following exposure, vascular endothelial function was assessed using forearm venous occlusion plethysmography and ex vivo thrombus formation was assessed using a Badimon chamber model of acute arterial injury. Biomarkers of inflammation, platelet activation and fibrinolysis were measured in the blood. Results In study 1, PDE and RME30 exposures were at comparable PM levels (314 ± 27 μg/m3; (PM10 ± SD) and 309 ± 30 μg/m3 respectively), whereas in study 2, the PDE exposure concentrations remained similar (310 ± 34 μg/m3), but RME100 levels were lower in PM (165 ± 16 μg/m3) and PAHs, but higher in particle number concentration. Compared to PDE, PM from RME had less oxidative potential. Forearm infusion of the vasodilators acetylcholine, bradykinin, sodium nitroprusside and verapamil resulted in dose-dependent increases in blood flow after all exposures. Vasodilatation and ex vivo thrombus formation were similar following exposure to exhaust from petrodiesel and the two biodiesel formulations (RME30 and RME100). There were no significant differences in blood biomarkers or exhaled nitric oxide levels between exposures. Conclusions Despite differences in PM composition and particle reactivity, controlled exposure to biodiesel exhaust was associated with similar cardiovascular effects to PDE. We suggest that the potential adverse health effects of biodiesel fuel emissions should be taken into account when evaluating future fuel policies. Trial registration ClinicalTrials.gov, NCT01337882 /NCT01883466. Date of first enrollment March 11, 2011, registered April 19, 2011, i.e. retrospectively registered

Rheology of the mortar phase of concrete with crushed aggregate

In Sweden, concrete has traditionally been manufactured with glaciofluvial deposits as fine aggregate. In 2004 the production of this aggregate was approximately 21 million tons. Due to environmental reasons and local shortage of this natural resource there exists a goal to reduce the production to 12 million tons in year 2010. In order to compensate for the reduced production an alternative material which can be used as replacement has to be found. Aggregate from crushed bedrock is an alternative which is locally available and found in sufficient amounts. However, the characteristics of this type of aggregate generally differ from the ones of glaciofluvial fine aggregate and are known to generate concrete with higher water demand and lower workability. In order to facilitate a changeover to crushed fine aggregate, it is important to achieve a better understanding of the influence of crushed fine aggregate characteristics on the workability of concrete. The properties of the mortar phase of concrete influence the workability of concrete. The study of the mortar phase of concrete with crushed fine aggregate can therefore be valuable in predicting the influence of the fine aggregate characteristics on concrete workability. The aim of this licentiate thesis was to clarify the influence of the characteristics of crushed fine aggregate (0-2 mm) on the rheological properties of mortars. This included studies of the effect of aggregate shape, quality and amount of fines, washed fine aggregate and superplasticizer addition. The experimental work was divided into three different parts, i.e., zeta potential study, micromortar and mortar rheology. In the zeta potential part, the interaction between different fines and a common type of superplasticizer was studied. The results indicate that the superplasticizer is preferentially adsorbed on biotite rich fines. In the micromortar part, the fines fraction of different fine aggregates was studied separately in order to evaluate the influence of their particle shape, specific surface area and mineral composition. The results from this part showed that the quality of the fines has a large influence on the rheological properties of micromortars. Furthermore, the yield stress and plastic viscosity were shown to increase with the specific surface area of the fines. The results also suggest that the shape of the fines mainly influences the plastic viscosity, i.e., the viscosity of the micromortars with elongated fines was higher than the corresponding micromortars with cubic shaped fines. In the mortar part, different fine aggregates were studied both with their original and with standardized grading curves. The evaluation was done both with and without addition of superplasticizer and at different paste volumes. The effect of washed fine aggregate was also evaluated. The results show that the shape of the fine aggregate particles mainly influences the plastic viscosity of the mortar. The fines content was shown to increase the yield stress and, thus, the water demand of the mortar. Furthermore, the results showed that washing and the use of superplasticizer are two potential ways to reduce the water demand of mortars with fine aggregates from crushed rock. Finally, the results from this work suggests that the higher yield stress and plastic viscosity often shown by mortars containing crushed fine aggregate can be related to two main characteristics of the aggregate. The high yield stress is believed to mainly originate from the high amounts of fines often seen in crushed fine aggregates, while the higher plastic viscosity can be related to the more elongated particle shape of the fine aggregate.Godkänd; 2006; 20070109 (haneit

Simulatorövningar i samband med MRM-kurs

Detta examensarbete vill klarlägga, hur man kan utnyttja The Swedish Club’s Maritime Resource Management (=MRM) – kursens moduler, vid övningar med Aboa Mares simulatorer. Arbetet vill även presentera exempelövningar för simulatormiljö. På basen av våra erfarenheter har vi sammanställt ett elektroniskt frågeformular, för undersökningens behov. Det finns med som bilaga i slutet av arbetet. Arbetet har begränsats till att omfatta endast däcksbefäl. Examensarbetet vill redogöra hur simulatorövningar kunde förbättra MRM-kursens innehåll, och hur väl övningarna motsvarar kursens teoretiska utbud. På basen av detta vill vi skapa kursmaterial, som fungerar väl vid simulatorövningarna. Undersökningen baserar sig på material, som definierats av The Swedish Club kurs, Aboa Mares läroplan, litteratur kring temat, lagar och förordningar, samt resultaten av utfrågningen. MRM-kursen har existerat redan I over tjugo år, och finns tillgänglig i många olika former, erbjuden av många olika arrangörer, jorden runt. Nya internationella regelverk har gjort Bridge Resource Management- utbildningen obligatorisk för däcks- och maskinbefäl. Respondenterna anser att examensarbetets tema är mycket viktigt och aktuellt.This thesis focuses on how the Maritime Resource Management courses modules (organized by The Swedish Club) can be exploited in Aboa Mare's simulator exercises. In addition there will be example exercises for the simulation environment. There is an electronic questionnaire tailored for the research attached in the end of the thesis. The work is limited to focus only on the deck officers. The aim of the thesis is to discover how one could improve the Maritime Resource Management course with simulator exercises and to study how the exercises work together with the taught theories. In addition it aims to create working material. The material is based on The Swedish Club's defined course material, Aboa Mare's syllabus, literature concerning the subject, regulations and laws, and surveys. Maritime Resource Management course has existed for over 20 years and the course is available all over the world by different service providers. With the newest STCW regulations Bridge Resource Management's education has become compulsory for deck- and engine officers. The creators of the thesis consider the subject very important at this time

Washing of aggregates : Influence on aggregate properties and mortar rheology

Aggregates (0-2 mm) produced by blasting and cruching of bedrock often contains rough and flaky particles with free mica and other minerals in finer fractions. Consequently, concrete produced with this type of aggregate displays a higher water demand and lower workability than the corresponding concrete with glaciofluvial aggregate. In order to achieve the desired workability changes in the mix design and/or processing of the aggregate, e.g. sieving and washing, are required. In this paper, the effect of washing on the material properties, i.e., particle size distribution, specific surface area and sand equivalent value (SE-value), of aggregates from crushed bedrock has been studied. The effect of the washed aggregates on the water demand of mortars was also studied with rheological methods. The results show that the used washing procedure mainly removed particles below 125 µm with emphasis on particles smaller than 40 µm. Consequently, this resulted in a decrease in the specific surface area of the fine particles and, thus, a lower water demand of the mortar. This is verified in the mortar tests where the yield stress of mortars was significantly reduced when the washed aggregates were used. Godkänd; 2006; 20071121 (palle)</p

Washing of aggregates : Influence on aggregate properties and mortar rheology

Aggregates (0-2 mm) produced by blasting and cruching of bedrock often contains rough and flaky particles with free mica and other minerals in finer fractions. Consequently, concrete produced with this type of aggregate displays a higher water demand and lower workability than the corresponding concrete with glaciofluvial aggregate. In order to achieve the desired workability changes in the mix design and/or processing of the aggregate, e.g. sieving and washing, are required. In this paper, the effect of washing on the material properties, i.e., particle size distribution, specific surface area and sand equivalent value (SE-value), of aggregates from crushed bedrock has been studied. The effect of the washed aggregates on the water demand of mortars was also studied with rheological methods. The results show that the used washing procedure mainly removed particles below 125 µm with emphasis on particles smaller than 40 µm. Consequently, this resulted in a decrease in the specific surface area of the fine particles and, thus, a lower water demand of the mortar. This is verified in the mortar tests where the yield stress of mortars was significantly reduced when the washed aggregates were used. Godkänd; 2006; 20071121 (palle)</p

FRA-lagen medför massiv kartläggning av oskyldiga

Mark Klamberg Doktorand juridik, Stockholms universitet, Mikael Nilsson Doktorand datalogi, Kungliga Tekniska högskolan, Anna Petersson Doktorand matematik, Uppsala universitet, Peter Seipel Professor emeritus rättsinformatik, Stockholms universitet, Janne Flyghed Professor kriminologi, Stockholms universitet, Cecilia Magnusson Sjöberg Professor i rättsinformatik, Stockholms universitet, Jussi Karlgren Docent språkteknologi, Swedish Institute of Computer Science, Markus Bylund Doktor i data- och systemvetenskap inriktning personlig integritet, Swedish Institute of Computer Science, Karl Palmås Civilingenjör och doktor i sociologi, Handelshögskolan vid Göteborgs universitet, Christopher Kullenberg Doktorand vetenskapsteori, Göteborgs universitet, Pär Ström Civilingenjör och författare, integritetsombudsman på tankesmedjan Den nya välfärden, Daniel Thorburn Professor i statistik, Stockholms universitet, Johan Westerholm Kapten, reservofficerare underrättelsetjänst, rådgivare Greyca