2,313 research outputs found

    Massive low surface brightness galaxies

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    A multi-wavelength study of an extreme type of galaxy which will assist us in our attempts to understand the formation and evolution of galaxies was completed. In particular, a subset of low surface brightness (bar-mu(sub B) is approximately greater than 25 mag arcsec(sup -2)), giant galaxies (LSBG's) which contain large amounts of atomic gas (M(HI) is approximately greater than 10(exp 10) solar mass), have blue optical diameters similar to those of giant spiral galaxies, but which do not seem to have prodigious amounts of ongoing star formation were observed. Our sample was drawn from the first and second Palomar Sky Surveys. This population of galaxies has been largely ignored because of selection effects which make it difficult to detect optically. The question of how these massive systems differ from the higher surface brightness 'normal' spiral galaxies is addressed. Using B and R surface photometry, in conjunction with H-alpha, HI, CO-12, and far-infrared data, an attempt is made to determine if these galaxies had an early epoch of star formation that has since faded, have ongoing star formation with an unusual interplanetary magnetic field (IMF), or are perhaps galaxies which have never efficiently formed stars due to a lack of molecular clouds

    Experimental study of the ageing of building stones exposed to sulfurous and nitric acid atmospheres

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    During the last few decades, due to remediation procedures, SO2 emissions in the atmosphere have decreased, unlike NOx. Air pollution has changed. Indeed, the aim of this research is to assess the effect of NOx and their interactions with SO2 on stones, particularly on limestones used in Champagne-Ardenne (France) during the restoration processes. Three French building limestones (Courville, Dom and Savonnières) and one reconstituted stone were exposed during 28 days to four strong acid atmospheres i.e. two H2SO3 solutions with different concentrations and two mixed atmospheres with different proportions of HNO3 and H2SO3. These tests produced an intensive acid attack on the stone, allowing the observation of short-term salt precipitation and the evolution of stone properties. Each day, one sample was removed from the acid atmosphere to measure the concentration of SO4(2-) and NO3(-) by ion-chromatography. The surface changes were assessed before and after the tests by 3D scanning and observations with electron microscopy. X-ray microtomography has been performed in the Centre for X-ray Tomography (UGCT) and the Department of Geology at Ghent University (Belgium) in order to observe the penetration of salts and the consequences in stones porosity. First observations showed that exposure to acid atmosphere, led to gypsum efflorescences. Obvious colour changes occurred in all tests. Salt crystallization entailed a change in the porous system, which was evidenced by 3D, mercury porosimetry and X-ray microtomography. Difference between weathered and fresh stone was highlighted by Ion chromatography analyses

    Der Beitrag internationaler Gerichte zur Zivilisierung des Konfliktaustrags

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    Comparing Practical Theology across Religions and Denominations

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    This is an Author’s Original Manuscript of an article submitted for consideration to the Review of Religious Research [copyright Springer]. The final publication is available at http://link.springer.com.While significant research and practice has examined congregational involvement in providing for those in need, few have looked at the denominational theology that informs these initiatives or influences the non-profit systems created to provide them. Drawing on ethnographic research from the Faith and Organizations project, a national research/practice initiative designed to explore the relationship between religions and faith based organizations, this paper compares the practical theology behind stewardship of social welfare and educational programs for Catholics, Mainline Protestants, Evangelicals, Jews, Quakers and African American Christians. The paper returns to older, expanded definitions of stewardship and provides identifies three stewardship systems based on religious practical theology. It observes strengths and weaknesses of each system and offers practical suggestions for strengthening connections between faith communities and FBOs in each syste

    A Classroom Experiment on Exchange Rate Determination with Purchasing Power Parity

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    We develop a classroom experiment on exchange rate determination appropriate for undergraduate courses in macroeconomics and international economics. Students represent citizens from different countries and need to obtain currency to purchase goods. By participating in a sealed bid auction to buy currency, students gain a better understanding of currency markets and the determination of exchange rates. The implicit framework for exchange rate determination is one in which prices are perfectly flexible (in the long run) so that purchasing power parity (PPP) prevails. Additional treatments allow students to examine the impact of transport costs, nontradable goods and tariffs on the exchange rate and to explore possible deviations from PPP.

    Differential marking in Kinande

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    This work presents newly-discovered data involving differential marking in the Bantu language Kinande (JD42), which affects three classes: (i) goals and sources; (ii) predicative possession; (iii) external possession. These patterns reveal important insights into the nature of differential marking in Bantu. First, typical differential marking features like animacy, definiteness, and person can involve a morphological difference on a \textit{dependen

    Research Design, Soil and Biodiversity Baseline for Long-term Farming Systems Comparison of Full Sun and Shaded Agroforestry Cocoa Production under Conventional and Organic Management in Alto Beni, Bolivia

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    Cocoa, mainly produced by 5 to 6 millions of smallholder farmers, is considered as one of the most sustainable production system in the humid tropics. Little is known about the sustainability of different cocoa production systems. A long-term experiment is set up in Alto Beni at 400m above sea level with a humid winter dry climate, 1’540 mm annual rainfall. The trial assesses the sustainability of five cocoa (Theobroma cacao) production systems with the parameters of yield and yield stability, input-output efficiency of nutrients and energy, soil fertility, biodiversity, economic result, climate change mitigation and adaptation. The two-factorial experiment is arranged in an completely randomised block design; the five cocoa treatments, based on local and international practices, are four times repeated. The production systems are differentiated by the diversity of shade canopy and by crops, from mono culture full sun cocoa to a agroforestry cocoa with leguminous species (Inga edulis, Erythrina poeppigiana) shade canopy, including fruits (e.g. Euterpe precatoria, Theobroma grandiflorum) and timber (e.g. Centrolobium ochroxylum, Swietenia macrophylla) species, and a higher diversified agroforestry system based on the natural successions of species. The management of the cocoa is conventional and organic. The five treatments are: mono culture full sun cocoa conventional, mono culture full sun organic, agroforestry conventional, agroforestry organic and successional agroforestry organic. Fallow plots and nearby forests plots are monitored for soil fertility and biodiversity. Field clearing started in 2007 followed by maize (Zea mays) crop and end of 2008 the cocoa plots (48m×48 m) were established. The results of the baseline studies concerning soil fertility show good nutrient level for cocoa production; the variance of soil parameters is documented in a soil map. According the FAO soil classification (2006) the soils are Lixisole and Luvisole with high base saturation

    Virus-like particles adsorption in anion exchange chromatography media

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    Biotechnological and pharmaceutical industries have the development of modern vaccines and novel drug delivery systems as one of their main focus. At this point, Virus-Like Particles (VLPs) are key candidates once they have the ability to stimulate humoral and cellular immune responses combined with the inability to replicate or proliferate. VLPs are non-infectious self-assembled protein structures which mimic native viruses (lacking any viral genetic material). However great developments in VLPs manufacturing have already been achieved, their purification is still a complex process, usually slow and with low productivity. Accordingly, there is a demand for new purification strategies and unit operations. Anion exchange chromatography is well established and widely used in industry for the purification all sorts of biomolecules. It is already known that polymer-grafted media in form of charged hydrogels and/or chromatography beads have a very high protein binding capacity and they also bind large biomolecules such as plasmids and viruses. However, the separation mechanism of large biomolecules is still not well understood and this lack of knowledge hinders the development and optimization of the purification processes. To overcome this, our aim is to elucidate the adsorption mechanisms of VLPs, large proteins and protein superstructures into different types of anion exchange chromatography media including highly charged hydrogels and polymer-grafted media. The binding kinetics and equilibria of HIV-1 VLPs expressed in CHO cells and Influenza VLPs expressed in Baculovirus-Insect cell system have been measured for polymer grafted media to elucidate the effect of the charged polymer. Adsorption isotherms were measured in microtiter plates and kinetics in batch mode. Gerster, P., Kopecky, E.-M., Hammerschmidt, N., Klausberger, M., Krammer, F., Grabherr, R., Mersich, C., Urbas, L., Kramberger, P., Paril, T., Schreiner, M., Nöbauer, K., Razzazi-Fazeli, E., Jungbauer, A. Purification of infective baculoviruses by monoliths (2013) Journal of Chromatography A, 1290, 36-45. Jungbauer, A., Hahn, R. Polymethacrylate monoliths for preparative and industrial separation of biomolecular assemblies (2008) Journal of Chromatography A, 1184 (1-2), 62-79. Jungbauer, A. Chromatographic media for bioseparation (2005) Journal of Chromatography A, 1065 (1), 3-12
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