Institution
University of Iceland
Education•Reykjavik, Suðurnes, Iceland•
About: University of Iceland is a education organization based out in Reykjavik, Suðurnes, Iceland. It is known for research contribution in the topics: Population & Genome-wide association study. The organization has 5423 authors who have published 16199 publications receiving 694762 citations. The organization is also known as: Háskóli Íslands.
Papers published on a yearly basis
Papers
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TL;DR: The fertilization potential of newly erupted and well-preserved ash from the 2000 Hekla eruption in Iceland was measured for the first time by flow-through experiments as mentioned in this paper.
Abstract: The fertilization potential of newly erupted and well-preserved ash from the 2000 Hekla eruption in Iceland was measured for the first time by flow-through experiments. As previously shown, (1) the North Atlantic Ocean, including the subarctic seas surrounding Iceland, is the largest net sink of the world’s oceans for atmospheric CO 2, owing to biological drawdown during summer; (2) almost complete consumption of phosphate in chlorophyll-rich areas of the North Atlantic Ocean might limit primary production; and (3) in the southern Pacific Ocean and parts of the equatorial Pacific Ocean iron might limit primary production. We found through laboratory experiments that volcanic ash exposed to seawater initially releases large amounts of adsorbed phosphate, 1.7 mmol·g 21 ·h 21 ; iron, 37.0 mmol·g 21 ·h 21 ; silica, 49.5 mmol·g 21 h 21 ; and manganese, 1.7 mmol·g 21 ·h 21 . Dissolution of acid aerosols adsorbed to the surface of the ash caused the high initial release of major and trace elements. Because of the instantaneous dissolution of adsorbed components when newly erupted volcanic ash comes in contact with the ocean surface water, macronutrients and ‘‘bioactive’’ trace metals are released fast enough to become available to support primary production.
268 citations
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TL;DR: This paper presents two novel methods for segmentation of images based on the Fractional-Order Darwinian Particle Swarm Optimization (FODPSO) and Darwinian particle Swarmoptimization for determining the n-1 optimal n-level threshold on a given image.
Abstract: Image segmentation has been widely used in document image analysis for extraction of printed characters, map processing in order to find lines, legends, and characters, topological features extraction for extraction of geographical information, and quality inspection of materials where defective parts must be delineated among many other applications. In image analysis, the efficient segmentation of images into meaningful objects is important for classification and object recognition. This paper presents two novel methods for segmentation of images based on the Fractional-Order Darwinian Particle Swarm Optimization (FODPSO) and Darwinian Particle Swarm Optimization (DPSO) for determining the n-1 optimal n-level threshold on a given image. The efficiency of the proposed methods is compared with other well-known thresholding segmentation methods. Experimental results show that the proposed methods perform better than other methods when considering a number of different measures.
267 citations
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TL;DR: The results indicate that drug/cyclodextrin complexes can self-associate to form water-soluble aggregates, which then can further solubilize the drug through non-inclusion complexation.
267 citations
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TL;DR: A framework based on Fickian theory as well as the Noyes-Whiney relationship is constructed to assess where cyclodextrins are likely to be useful and where their use is probably not justified in the context of BCS, a US FDA-based characterization approach that bins drugs based on solubility and permeability features.
Abstract: The use of high-throughput screening and similar techniques in drug discovery has put a number of evolutionary pressures on drug candidates such that over time there is a tendency for them to increase in molecular weight, increase in log K(octanol/water) and decrease in water solubility. These trends provide an ever-increasing series of challenges for the drug formulator to generate effective, orally bioavailable dosage forms. An important tool in this regard is the use of cyclodextrins, especially chemically modified cyclodextrins. These starch derivatives interact via dynamic complex formation and other mechanisms in a way that camouflages undesirable physicochemical properties, including low aqueous solubility, poor dissolution rate and limited drug stability. Through these effects, cyclodextrins and their derivatives have become popular modalities for increasing oral bioavailability and absorption rate. These actions have positioned cyclodextrins as important enabling and functional excipients. This review aims to assess the use of cyclodextrins in oral and other administration routes in the context of the Biopharmaceutical Classification Systems (BCS), a US FDA-based characterization approach that bins drugs based on solubility and permeability features. Specifically, a framework based on Fickian theory as well as the Noyes-Whiney relationship is constructed to assess where cyclodextrins are likely to be useful and where their use is probably not justified. This working model is examined in the context of a number of published examples in which cyclodextrins have been applied to class I, II, III, and IV drugs and drug candidates.
267 citations
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TL;DR: Vitrectomy and retinal photocoagulation both improve retinal oxygenation and both reduce diabetic macular edema and retina neovascularization.
Abstract: The physiologic mechanism of photocoagulation can been seen in the following steps. The physical light energy is absorbed in the melanin of the retinal pigment epithelium. The adjacent photoreceptors are destroyed and are replaced by a glial scar and the oxygen consumption of the outer retina is reduced. Oxygen that normally diffuses from the choriocapillaris into the retina can now diffuse through the laser scars in the photoreceptor layer without being consumed in the mitochondria of the photoreceptors. This oxygen flux reaches the inner retina to relieve inner retinal hypoxia and raise the oxygen tension. As a result, the retinal arteries constrict and the bloodflow decreases. Hypoxia relief reduces production of growth factors such as VEGF and neovascularization is reduced or stopped. Vasoconstriction increases arteriolar resistance, decreases hydrostatic pressure in capillaries and venules and reduces edema formation according to Starling's law. Vitrectomy also improves retinal oxygenation by allowing oxygen and other nutrients to be transported in water currents in the vitreous cavity from well oxygenated to ischemic areas of the retina. Vitrectomy and retinal photocoagulation both improve retinal oxygenation and both reduce diabetic macular edema and retinal neovascularization.
266 citations
Authors
Showing all 5561 results
Name | H-index | Papers | Citations |
---|---|---|---|
Albert Hofman | 267 | 2530 | 321405 |
Kari Stefansson | 206 | 794 | 174819 |
Ronald Klein | 194 | 1305 | 149140 |
Eric Boerwinkle | 183 | 1321 | 170971 |
Unnur Thorsteinsdottir | 167 | 444 | 121009 |
Vilmundur Gudnason | 159 | 837 | 123802 |
Hakon Hakonarson | 152 | 968 | 101604 |
Bernhard O. Palsson | 147 | 831 | 85051 |
Andrew T. Hattersley | 146 | 768 | 106949 |
Fernando Rivadeneira | 146 | 628 | 86582 |
Rattan Lal | 140 | 1383 | 87691 |
Jonathan G. Seidman | 137 | 563 | 89782 |
Christine E. Seidman | 134 | 519 | 67895 |
Augustine Kong | 134 | 237 | 89818 |
Timothy M. Frayling | 133 | 500 | 100344 |