Institution
Stockholm University
Education•Stockholm, Sweden•
About: Stockholm University is a education organization based out in Stockholm, Sweden. It is known for research contribution in the topics: Population & Supernova. The organization has 21052 authors who have published 62567 publications receiving 2725859 citations. The organization is also known as: University of Stockholm & Stockholms universitet.
Topics: Population, Supernova, Galaxy, Large Hadron Collider, Arctic
Papers published on a yearly basis
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TL;DR: An analysis of the geochemical conditions under which nitrogenase evolved is presented and how the evolutionary history of the enzyme complex corresponds to the physiological, morphological, and developmental strategies for reducing damage by molecular oxygen is examined.
466 citations
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TL;DR: It is concluded that it is important to improve the knowledge of toxic interactions among the different chemicals and to develop measures for combined exposure to various groups of phthalates.
Abstract: The purposes of this review are to (1) evaluate human and experimental evidence for adverse effects on reproduction and development in humans, produced by exposure to phthalates, and (2) identify knowledge gaps as for future studies. The widespread use of phthalates in consumer products leads to ubiquitous and constant exposure of humans to these chemicals. Phthalates were postulated to produce endocrine-disrupting effects in rodents, where fetal exposure to these compounds was found to induce developmental and reproductive toxicity. The adverse effects observed in rodent models raised concerns as to whether exposure to phthalates represents a potential health risk to humans. At present, di(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP), and butyl benzyl phthalate (BBP) have been demonstrated to produce reproductive and developmental toxicity; thus, this review focuses on these chemicals. For the general population, DEHP exposure is predominantly via food. The average concentrations of phthalates are highest in children and decrease with age. At present, DEHP exposures in the general population appear to be close to the tolerable daily intake (TDI), suggesting that at least some individuals exceed the TDI. In addition, specific high-risk groups exist with internal levels that are several orders of magnitude above average. Urinary metabolites used as biomarkers for the internal levels provide additional means to determine more specifically phthalate exposure levels in both general and high-risk populations. However, exposure data are not consistent and there are indications that secondary metabolites may be more accurate indicators of the internal exposure compared to primary metabolites. The present human toxicity data are not sufficient for evaluating the occurrence of reproductive effects following phthalate exposure in humans, based on existing relevant animal data. This is especially the case for data on female reproductive toxicity, which are scarce. Therefore, future research needs to focus on developmental and reproductive endpoints in humans. It should be noted that phthalates occur in mixtures but most toxicological information is based on single compounds. Thus, it is concluded that it is important to improve the knowledge of toxic interactions among the different chemicals and to develop measures for combined exposure to various groups of phthalates.
465 citations
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TL;DR: In this paper, the authors discuss the relation between economic growth and environmental quality, and the link between economic activity and the carrying capacity and resilience of the environment (e.g., water quality).
465 citations
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Royal Swedish Academy of Sciences1, Stockholm University2, Stanford University3, WorldFish4, Dalhousie University5, Columbia University6, Princeton University7, University of Oslo8, University of Minnesota9, Wageningen University and Research Centre10, Commonwealth Scientific and Industrial Research Organisation11, Athens University of Economics and Business12, Tilburg University13
TL;DR: This work explores how current interconnections between the aquaculture, crop, livestock, and fisheries sectors act as an impediment to, or an opportunity for, enhanced resilience in the global food system given increased resource scarcity and climate change.
Abstract: Aquaculture is the fastest growing food sector and continues to expand alongside terrestrial crop and livestock production. Using portfolio theory as a conceptual framework, we explore how current interconnections between the aquaculture, crop, livestock, and fisheries sectors act as an impediment to, or an opportunity for, enhanced resilience in the global food system given increased resource scarcity and climate change. Aquaculture can potentially enhance resilience through improved resource use efficiencies and increased diversification of farmed species, locales of production, and feeding strategies. However, aquaculture’s reliance on terrestrial crops and wild fish for feeds, its dependence on freshwater and land for culture sites, and its broad array of environmental impacts diminishes its ability to add resilience. Feeds for livestock and farmed fish that are fed rely largely on the same crops, although the fraction destined for aquaculture is presently small (∼4%). As demand for high-value fed aquaculture products grows, competition for these crops will also rise, as will the demand for wild fish as feed inputs. Many of these crops and forage fish are also consumed directly by humans and provide essential nutrition for low-income households. Their rising use in aquafeeds has the potential to increase price levels and volatility, worsening food insecurity among the most vulnerable populations. Although the diversification of global food production systems that includes aquaculture offers promise for enhanced resilience, such promise will not be realized if government policies fail to provide adequate incentives for resource efficiency, equity, and environmental protection.
465 citations
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TL;DR: This Account summarizes theoretical research to elucidate the mechanism for water oxidation in photosynthesis, including the most recent findings, and describes a low-barrier mechanism for formation of the O-O bond, involving an oxygen radical that reacts with a mu-oxo ligand of the oxygen evolving complex.
Abstract: Water oxidation, forming O2 from water and sunlight, is a fundamental process for life on earth. In nature, the enzyme photosystem II (PSII) catalyzes this reaction. The oxygen evolving complex (OEC), the complex within PSII that catalyzes the actual formation of the O−O bond, contains four manganese atoms and one calcium atom connected by oxo bonds. Seven amino acid side chains in the structure, mostly carboxylates, are ligated to the metal atoms. In the study of many enzyme mechanisms, theoretical modeling using density functional theory has served as an indispensable tool. This Account summarizes theoretical research to elucidate the mechanism for water oxidation in photosynthesis, including the most recent findings. The development of successively larger models, ranging from 50 atoms in the active site up to the present model size of 170 atoms, has revealed the mechanism of O2 formation with increasing detail. The X-ray crystal structures of PSII have provided a framework for optimizing the theoretica...
464 citations
Authors
Showing all 21326 results
Name | H-index | Papers | Citations |
---|---|---|---|
Hongjie Dai | 197 | 570 | 182579 |
Hyun-Chul Kim | 176 | 4076 | 183227 |
Richard S. Ellis | 169 | 882 | 136011 |
Stanley B. Prusiner | 168 | 745 | 97528 |
Anders Björklund | 165 | 769 | 84268 |
Yang Yang | 164 | 2704 | 144071 |
Tomas Hökfelt | 158 | 1033 | 95979 |
Bengt Winblad | 153 | 1240 | 101064 |
Zhenwei Yang | 150 | 956 | 109344 |
Marvin Johnson | 149 | 1827 | 119520 |
Jan-Åke Gustafsson | 147 | 1058 | 98804 |
Markus Ackermann | 146 | 610 | 71071 |
Hans-Olov Adami | 145 | 908 | 83473 |
Markku Kulmala | 142 | 1487 | 85179 |
Kjell Fuxe | 142 | 1479 | 89846 |