3,009 research outputs found
A Spatial Mathematical Model Analysis of the Linkage between Agricultural Trade and Deforestation
Like agricultural trade, deforestation has increased tremendously throughout the past five decades. We analyse the linkage between both factors by applying trade and forest policy scenarios to the global land-use model MAgPIE ("Model of Agricultural Production and its Impact on the Environment"). The model predicts global landuse patterns in a spatially explicit way and uses endogenously derived technological change and land expansion rates. Our study is the first which combines global trade analysis with a spatially explicit mapping of deforestation. By implementing self-sufficiency rates in the regional demand and supply equations, we are able to simulate different trade settings. Our baseline scenario fixes current trade patterns until the year 2045. The three liberalisation scenarios assume a path of increasing trade liberalisation which ends with no trade barriers in 2045 and they differ by applying different forest protection policies. Regions with comparative advantages like Latin America for oilcrops and China for cereals will export more. Whereas, Latin America will buy this competitiveness by converting large parts of its Amazonian rainforest into cropland, China will benefit most due to its decreasing food demand after 2025. In contrast, regions like the Middle East, North Africa and South Asia face the highest increases of imports. Forest protection policies lead to higher technological change rates. In absence of such policies, investments in agricultural Research & Development are the most effective way for protecting the forest.International Relations/Trade, Resource /Energy Economics and Policy,
FolkRank: A Ranking Algorithm for Folksonomies
In social bookmark tools users are setting up lightweight conceptual structures called folksonomies. Currently, the information retrieval support is limited. We present a formal model and a new search algorithm for folksonomies, called FolkRank, that exploits the structure of the folksonomy. The proposed algorithm is also applied to find communities within the folksonomy and is used to structure search results. All findings are demonstrated on a large scale dataset. A long version of this paper has been published at the European Semantic Web Conference 2006
Semantic Network Analysis of Ontologies
A key argument for modeling knowledge in ontologies is the easy re-use and re-engineering of the knowledge. However, current ontology engineering tools provide only basic functionalities for analyzing ontologies. Since ontologies can be considered as graphs, graph analysis techniques are a suitable answer for this need. Graph analysis has been performed by sociologists for over 60 years, and resulted in the vivid research area of Social Network Analysis (SNA). While social network structures currently receive high attention in the Semantic Web community, there are only very few SNA applications, and virtually none for analyzing the structure of ontologies. We illustrate the benefits of applying SNA to ontologies and the Semantic Web, and discuss which research topics arise on the edge between the two areas. In particular, we discuss how different notions of centrality describe the core content and structure of an ontology. From the rather simple notion of degree centrality over betweenness centrality to the more complex eigenvector centrality, we illustrate the insights these measures provide on two ontologies, which are different in purpose, scope, and size
Use of a plant-based polysaccharide hemostat for the treatment of sternal bleeding after median sternotomy
Background: In cardiac surgery profuse or persistent sternal bleeding after sternotomy is routinely controlled with bone wax. However, bone wax should be avoided, especially in high-risk patients for nonunion of the sternum and infections. Purpose of this study was to evaluate an alternative technique to control bleeding after medium sternotomy using a plant based absorbable polysaccharide hemostat. Methods: A consecutive series of 38 patients requiring median sternotomy for coronary artery bypass surgery (21 OPCAB, 17 CABG) had sternal bleeding control with the polysaccharide hemostat, STARSIL (R) HEMOSTAT. This hemostat is a hydrophilic powder, which achieves hemostasis after topical application at the surgical wound site. Initially it dehydrates blood rapidly, thus accelerating aggregation of platelets and blood solids. Thereafter, it forms a gelled adhesive matrix, which serves as a mechanical barrier against further bleeding. The polysaccharide is completely resorbed within 48 to 72 hours. Results: Satisfactory control of sternal bleeding was observed in 37 patients (97%). No product-related complications were observed or any other major adverse events in an observation period of 3 months. Conclusion: Polysaccharide hemostats appear to be safe and effective for bleeding control of the sternum
More than Ninety Percent of the Light Energy Emitted by Near-Infrared Laser Therapy Devices Used to Treat Musculoskeletal Disorders Is Absorbed within the First Ten Millimeters of Biological Tissue
There is increasing interest in the application of near-infrared (NIR) laser light for the treatment of various musculoskeletal disorders. The present study thoroughly examined the physical characteristics of laser beams from two different laser therapy devices that are commercially available for the treatment of musculoskeletal disorders. Then, these laser beams were used to measure the penetration depth in various biological tissues from different animal species. The key result of the present study was the finding that for all investigated tissues, most of the initial light energy was lost in the first one to two millimeters, more than 90% of the light energy was absorbed within the first ten millimeters, and there was hardly any light energy left after 15-20 mm of tissue. Furthermore, the investigated laser therapy devices fundamentally differed in several laser beam parameters that can have an influence on how light is transmitted through tissue. Overall, the present study showed that a laser therapy device that is supposed to reach deep layers of tissue for treatments of musculoskeletal disorders should operate with a wavelength between 800 nm and 905 nm, a top-hat beam profile, and it should emit very short pulses with a large peak power
Use of a plant-based polysaccharide hemostat for the treatment of sternal bleeding after median sternotomy
Background: In cardiac surgery profuse or persistent sternal bleeding after sternotomy is routinely controlled with bone wax. However, bone wax should be avoided, especially in high-risk patients for nonunion of the sternum and infections. Purpose of this study was to evaluate an alternative technique to control bleeding after medium sternotomy using a plant based absorbable polysaccharide hemostat. Methods: A consecutive series of 38 patients requiring median sternotomy for coronary artery bypass surgery (21 OPCAB, 17 CABG) had sternal bleeding control with the polysaccharide hemostat, STARSIL (R) HEMOSTAT. This hemostat is a hydrophilic powder, which achieves hemostasis after topical application at the surgical wound site. Initially it dehydrates blood rapidly, thus accelerating aggregation of platelets and blood solids. Thereafter, it forms a gelled adhesive matrix, which serves as a mechanical barrier against further bleeding. The polysaccharide is completely resorbed within 48 to 72 hours. Results: Satisfactory control of sternal bleeding was observed in 37 patients (97%). No product-related complications were observed or any other major adverse events in an observation period of 3 months. Conclusion: Polysaccharide hemostats appear to be safe and effective for bleeding control of the sternum
Implementing Bilateral Trade in a Global Landuse Model
International Relations/Trade, Land Economics/Use,
Некоторые особенности поведения урана и тория в вулканогенных образованиях северо-восточного горного обрамления Минусинской котловины
Обосновано отнесение девонских полифациальных изверженных пород основного, щелочного и кислого составов к двум генетически самостоятельным ассоциациям: базальт-фонолитовой и дацит-трахилипаритовой. Приведены содержания урана и тория в породах обеих ассоциаций, на основании чего сделаны выводы о поведении этих элементов в процессе эволюции родоначальных магм
High mobility dry-transferred CVD bilayer graphene
We report on the fabrication and characterization of high-quality chemical
vapor-deposited (CVD) bilayer graphene (BLG). In particular, we demonstrate
that CVD-grown BLG can mechanically be detached from the copper foil by an
hexagonal boron nitride (hBN) crystal after oxidation of the copper-to-BLG
interface. Confocal Raman spectroscopy reveals an AB-stacking order of the BLG
crystals and a high structural quality. From transport measurements on fully
encapsulated hBN/BLG/hBN Hall bar devices we extract charge carrier mobilities
up to 180,000 cm/(Vs) at 2 K and up to 40,000 cm/(Vs) at 300 K,
outperforming state-of-the-art CVD bilayer graphene devices. Moreover, we show
an on-off ration of more than 10,000 and a band gap opening with values of up
to 15 meV for a displacement field of 0.2 V/nm in such CVD grown BLG.Comment: 5 pages, 4 figure
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