| 1. |
- Appeltans, W., et al.
(författare)
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The Magnitude of Global Marine Species Diversity
- 2012
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Ingår i: Current Biology. - : Elsevier BV. - 0960-9822 .- 1879-0445. ; 22:23, s. 2189-2202
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Tidskriftsartikel (refereegranskat)abstract
- Background: The question of how many marine species exist is important because it provides a metric for how much we do and do not know about life in the oceans. We have compiled the first register of the marine species of the world and used this baseline to estimate how many more species, partitioned among all major eukaryotic groups, may be discovered. Results: There are similar to 226,000 eukaryotic marine species described. More species were described in the past decade (similar to 20,000) than in any previous one. The number of authors describing new species has been increasing at a faster rate than the number of new species described in the past six decades. We report that there are similar to 170,000 synonyms, that 58,000-72,000 species are collected but not yet described, and that 482,000-741,000 more species have yet to be sampled. Molecular methods may add tens of thousands of cryptic species. Thus, there may be 0.7-1.0 million marine species. Past rates of description of new species indicate there may be 0.5 +/- 0.2 million marine species. On average 37% (median 31%) of species in over 100 recent field studies around the world might be new to science. Conclusions: Currently, between one-third and two-thirds of marine species may be undescribed, and previous estimates of there being well over one million marine species appear highly unlikely. More species than ever before are being described annually by an increasing number of authors. If the current trend continues, most species will be discovered this century.
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| 2. |
- Daniau, A. -L, et al.
(författare)
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predictability of biomass burning in response to climate changes
- 2012
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Ingår i: Global Biogeochemical Cycles. - 0886-6236 .- 1944-9224. ; 26, s. GB4007-
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Tidskriftsartikel (refereegranskat)abstract
- Climate is an important control on biomass burning, but the sensitivity of fire to changes in temperature and moisture balance has not been quantified. We analyze sedimentary charcoal records to show that the changes in fire regime over the past 21,000 yrs are predictable from changes in regional climates. Analyses of paleo-fire data show that fire increases monotonically with changes in temperature and peaks at intermediate moisture levels, and that temperature is quantitatively the most important driver of changes in biomass burning over the past 21,000 yrs. Given that a similar relationship between climate drivers and fire emerges from analyses of the interannual variability in biomass burning shown by remote-sensing observations of month-by-month burnt area between 1996 and 2008, our results signal a serious cause for concern in the face of continuing global warming.
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| 3. |
- Blackwell, Simon E., et al.
(författare)
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Optimism and mental imagery : A possible cognitive marker to promote well-being?
- 2013
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Ingår i: Psychiatry Research. - : ELSEVIER IRELAND LTD. - 0165-1781 .- 1872-7123. ; 206:1, s. 56-61
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Tidskriftsartikel (refereegranskat)abstract
- Optimism is associated with a range of benefits not only for general well-being, but also for mental and physical health. The development of psychological interventions to boost optimism derived from cognitive science would have the potential to provide significant public health benefits, yet cognitive markers of optimism are little understood. The current study aimed to take a first step in this direction by identifying a cognitive marker for optimism that could provide a modifiable target for innovative interventions. In particular we predicted that the ability to generate vivid positive mental imagery of the future would be associated with dispositional optimism. A community sample of 237 participants completed a survey comprising measures of mental imagery and optimism, and socio-demographic information. Vividness of positive future imagery was significantly associated with optimism, even when adjusting for socio-demographic factors and everyday imagery use. The ability to generate vivid mental imagery of positive future events may provide a modifiable cognitive marker of optimism. Boosting positive future imagery could provide a cognitive target for treatment innovations to promote optimism, with implications for mental health and even physical well-being. (C) 2012 Elsevier Ireland Ltd. All rights reserved.
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| 4. |
- Sales, Claudomiro, et al.
(författare)
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Line Topology Identification Using Multiobjective Evolutionary Computation
- 2010
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456. ; 59:3, s. 715-729
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Tidskriftsartikel (refereegranskat)abstract
- The broadband capacity of the twisted-pair lines strongly varies within the copper access network. It is therefore important to assess the ability of a digital subscriber line (DSL) to support the DSL services prior to deployment. This task is handled by the line qualification procedures, where the identification of the line topology is an important part. This paper presents a new method, denoted topology identification via model-based evolutionary computation (TIMEC), for line topology identification, where either one-port measurements or both one-and two-port measurements are utilized. The measurements are input to a model-based multiobjective criterion that is minimized by a genetic algorithm to provide an estimate of the line topology. The inherent flexibility of TIMEC enables the incorporation of a priori information, e. g., the total line length. The performance of TIMEC is evaluated by computer simulations with varying degrees of information. Comparison with a state-of-art method indicates that TIMEC achieves better results for all the tested lines when only one-port measurements are used. The results are improved when employing both one-and two-port measurements. If a rough estimate of the total length is also used, near-perfect estimation is obtained for all the tested lines.
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