1,038 research outputs found
Seasonal population dynamics of the invasive polychaete genus Marenzelleria spp. in contrasting soft-sediment habitats
Three species of the invasive polychaete genus Marenzelleria are among the dominant benthic taxa in many, especially deeper, areas in the Baltic Sea. The population dynamics of the polychaetes in the Baltic are, however, still largely unknown. We conducted monthly samplings of the benthic communities and environmental parameters at five sites with differing depths and sediment characteristics in the northern Baltic Sea (59 degrees 50.896', 23 degrees 15.092') to study the population dynamics, productivity and growth of Marenzelleria spp. from April 2013 to June 2014. The species of Marenzelleria occurring at the study sites were identified by genetic analyses. At the deepest site (33 m) only M. arctia was present, while all three species were found at the shallower, muddy sites (up to 20 m depth). At the shallow (6 m) sandy site only M. viridis and M. neglecta occurred. The sites differed in the seasonal dynamics of the Marenzelleria spp. population, reflecting the different species identities. The muddy sites up to 20 m depth showed clear seasonal dynamics, with the population practically disappearing by winter, whereas more stable populations occurred at the deepest site and at the sandy site. The highest density, biomass and production were observed at the 20 m deep, organic-rich muddy site where all three species recruited. The seasonally very high densities are likely to have important consequences for organic matter processing, and species interactions at these sites. The observed high productivity of the populations has possibly facilitated their establishment, and considerably increased secondary production in especially the deeper areas.Peer reviewe
Acidification in Europe : A Simulation Model for Evaluating Control Strategies
RAINS (Regional Acidification Information and Simulation) is an integrated model of acidification in Europe designed as a tool for evaluating control strategies. It is currently sulfur-based, but is being expanded to include nitrogen species. Emphasis of the model is on the transboundary aspects of the acidification problem. Model computations are performed on a personal computer. Linked submodels are available for SO2 emissions, cost of control strategies, atmospheric transport of sulfur, forest soil and groundwater acidity, lake acidification, and the direct impact of SO2 on forests. The model can be used for scenario analysis, where the user prescribes a control strategy and then examines the cost and environmental consequences of this strategy, or for optimization analysis, in which the user sets cost and deposition goals, and identifies an "optimal" sulfur-reduction strategy. Preliminary use of the model has pointed to 1. the importance of examining long-term environmental consequences of control strategies, and 2. the cost advantages of a cooperative European sulfur-reduction program
Monetäre Bewertung der wirtschaftlichen Folgen neuartiger Waldschäden anhand internationaler Daten
Vortrag im Symposium über Bewertung von Waldschäden infolge von Luftverunreinigungen. Gmunden, Österreich 13. -17. September 1988. IUFRO Arbeitsgruppe S4.04. -02
Weathering of Viama?o granodiorite, south Brazil : Part 2-Initial porosity of un-weathered rock controls porosity development in the critical zone
The development of porosity during rock weathering is a key process controlling nutrients release, water holding capacity available for plants and water flow. Here we used X-ray Computed Tomography (XRCT) and 14C PolyMethylMethAcrylate (PMMA) autoradiography to show how cracks are created and enlarged during initial weathering stages (saprock and saprolite) of granodiorite in southern Brazil (Viama similar to o - RS). The physical evolution is characterized by imaging the pore network, using 14C-PMMA and XRCT methods. Combined with bulk porosity measurements, they highlight the increase in porosity with the degree of weathering (un-weathered rock phi = 1.66 %, saprolite phi = 11.7 %). This increase is related to the joint increase of the density of the cracks (unweathered rock D = 0.28 mm-1, saprolite D = 0.94 mm-1) and of the average opening of the microcracks (unweathered rock w = 2.4 mu m, saprolite w = 3.9 mu m) and macrocracks (un-weathered rock w = 176 mu m, saprolite w = 400 mu m). However, these average crack openings do not account for the variability of the openings that govern the flows, characterized here by specific distribution ranging from the submicrometre to the centimetre scale. The results highlight that the pore network of the un-weathered rock plays a key role in the initial stages or incipient weathering. The density and aperture and cracks increase following the subcritical cracking concept and new pores are formed by chemo-mechanical processes. The presence/absence of initial fractures in the regolith is certainly a key parameter controlling the weathering of different rock types (mafic vs felsic).Peer reviewe
Integration of African firms into global value chains
Ever since the emergence of the global sourcing and manufacturing phenomenon, numerous firms have expanded their sourcing and manufacturing efforts to low-cost countries to increase their competitive advantage. However, as costs are drastically rising in previously cost-efficient countries, firms in both low-cost and high-cost countries are experiencing continental shifts in global sourcing and manufacturing patterns. On the one hand, firms from developed economies are gradually leaving previously cost-efficient sourcing destinations, such as China, to search for suppliers in alternative low-cost locations, such as the African continent, or reshoring to their home countries. On the other hand, firms from relatively low-cost economies, such as China, are also increasingly starting to source from other destinations, such as the African continent, and offshore their manufacturing activities to high-cost environments.Â
To facilitate a scientific treatment of the continental shifts in global sourcing and manufacturing, this dissertation focuses on the topic from the perspectives of China and Africa. Specifically, this dissertation investigates the challenges faced by Chinese manufacturing suppliers, and their responses, in supplying to global buyers, and the factors motivating Chinese firms to offshore their manufacturing to high-cost environments. Additionally, this dissertation takes a deeper look into the gaps in extant literature on sourcing from Africa and suggests future research avenues. Finally, yet importantly, this dissertation identifies the roles of African suppliers in global value chains as well as the motives of firms from both developed and developing economies in sourcing from Africa and the common obstacles met.Â
The overall findings of this dissertation reveal that the roles of Chinese and African firms have changed in global value chains, with China moving up the value ladder and Africa becoming more integrated. The findings also indicate that there are no overarching "etic" theories (i.e. general theories which everyone can transpose and adapt for their specific conditions, as opposed to "emic" theories which are contextual and suitable only for specific situations (Revilla and Sáenz, 2014)) in the purchasing and supply management discipline that can be applied regardless of national and cultural contexts, as it has been found that extant knowledge of theories and frameworks on global sourcing and manufacturing cannot necessarily be applied in the Chinese and African contexts
Sourcing from Africa: A Systematic Review and a Research Agenda
Finnish Foundation for Economic Educatio
The sustainability challenge of meeting carbon dioxide targets in Europe by 2020
Final draft version (post-refereeing). Archived with permission from Elsevier.Following the Kyoto Protocol, the European Union obligated itself to lower its greenhouse gas (GHG) emissions 20% below their 1990 level, by the year 2020. Carbon dioxide is the major GHG. To fulfill this obligation, the nations must meet the sustainability challenge of countering rising population plus affluence with the dematerialization of less energy per GDP plus the decarbonization of less carbon per energy. To test the feasibility of meeting the challenge, we analyzed carbon dioxide emission during 1993–2004. Although emissions in the entire Union grew only by an average of 0.31% per year, emissions and their drivers varied markedly among the 27 member states. Dematerialization and decarbonization did occur, but not enough to offset the slight population growth plus rapidly increasing affluence. To fulfill its obligation in the next 12 years, the EU27 would have to counter its increasing population and affluence by a combined dematerialization and decarbonization 1.9–2.6 times faster than during 1993–2004. Hence, fulfilling its obligation by addressing fossil carbon emissions alone is very unlikely
Healthcare costs and outcomes in adult patients with juvenile idiopathic arthritis : a population-based study
Objectives: Evidence of the economic burden and long-term outcomes of juvenile idiopathic arthritis (JIA) remains scarce. Our aim was to explore healthcare costs and long-term outcomes in adult patients with JIA. Method: We identified all adult patients (>= 18 years) with JIA who visited Jyvaskyla Central Hospital rheumatology unit between May 2007 and March 2016. We considered individual medians of time-dependent clinical variables. These data were linked to administrative data from the area from the fiscal year 2014, which include information on all public healthcare contacts. Healthcare utilization is presented as direct costs in euros (EUR). Factors affecting direct costs were assessed with a generalized linear model. Results: In 218 patients, median 28-joint Disease Activity Score with three variables (DAS28-3) was = 30 years, and median Health Assessment Questionnaire (HAQ) score was <0.5 in 85.7% and 45.4%, respectively. In the utilization data (four municipalities, 137 patients), the total annual health services-related direct costs were 432 257 EUR (mean = 3155 EUR/patient/year). Thirty-six patients (26.3%) used biological disease-modifying anti-rheumatic drugs (bDMARDs) in 2014 for a total of 355 months, and the annual cost of bDMARDs was estimated at 355 000 EUR. Those with active disease had mean costs 2.4-fold higher than those with low or no disease activity. A one-point increase in median raw HAQ incurred an average 228 EUR increase in annual costs (p = 0.03). Conclusion: Most adult patients with JIA seem to manage well with their arthritis, bearing in mind that there still is room for improvement in long-term outcomes.Peer reviewe
Psoriatic arthritis, axial spondyloarthritis and rheumatoid arthritis in Norway : nationwide prevalence and use of biologic agents
Objective To estimate the prevalence of psoriatic arthritis (PsA), axial spondyloarthritis (axSpA) and rheumatoid arthritis (RA) and the use of biologic agents in these diseases in Norway. Methods From the Norwegian Patient Registry (NPR), we identified as PsA, axSpA and RA patients >= 18 years those with >= 2 recorded episodes with diagnostic coding for index disease (L40.5, M07.0-M07.3 for PsA; M45, M46.0, M46.1, M46.8 and M46.9 for axSpA; M05-M06 for RA). We calculated the point prevalence of PsA, axSpA and RA as per the 1(st) of January 2017 in the Norwegian adult population (age >= 18). Dispensed disease-modifying antirheumatic drug (DMARD) prescriptions were obtained from the Norwegian Prescription Database and biologic DMARDs given in hospitals from the NPR. Results The point prevalence of PsA, axSpA, RA, and any of these diseases in total was 0.46%, 0.41%, 0.78%, and 1.56%, respectively. Among women, the prevalence of PsA, axSpA, and RA was 0.50%, 0.37%, and 1.10%, and among men 0.43%, 0.45%, and 0.46%, respectively. In 2017, 27.3% of RA patients, 25.7% of PsA patients and 35.1% of axSpA patients used biologic DMARDs. Treatment with biologics was more frequent in younger age groups in all three diseases, and became more infrequent especially after age >= 55 years. Conclusion In Norway, the combined prevalence of PsA, axSpA, and RA was over 1.5%. Reflecting the good overall access to highly effective but costly biologic treatments, more than a fourth of these patients used biologic agents, which corresponds to over 0.4% of Norwegian adult population.Peer reviewe
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