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George F. Forsey 《Journal of Natural History》2013,47(25-28):1833-1864
Mutualism is an interactive, mutually beneficial relationship between two or rarely more unrelated taxa. It is ubiquitous in most environments. In the marine environment it is most likely to occur in shallow marine, oligotrophic regions, the open marine photic zone and oxygen-limited environments. Whereas the eukaryote cell is of some antiquity, other mutualisms may have been acquired during the Phanerozoic. The fossil record provides inferential evidence for the minimum time of origin and occurrence of mutualisms. This suggests that a variety of mutualisms may have occurred during the Palaeozoic with most apparently being terminated by the Permian mass extinction. Tracing back the origin of extant mutualisms suggests that the majority of these began in the Mesozoic or Cenozoic and indicate an increase to the present day. Whether the increase in mutualisms is a product of increased biodiversity or whether mutualisms may have partly driven biodiversity is unclear. 相似文献
344.
Chryssi Mytilineou Aikaterini Anastasopoulou George Christides Petros Bekas Chris J. Smith Konstantia N. Papadopoulou 《Journal of Natural History》2013,47(25-28):1645-1662
We report new species records and information related to meristic, morphometric, bathymetric and biological characteristics that increase our knowledge of the deep ichthyofauna of the Ionian Sea (E. Mediterranean). The material was collected with long lines from 300 to 800 m deep in the Eastern Ionian Sea in June and October 2010. The fish species Schedophilus ovalis (Cuvier, 1833) (Osteichthyes: Centrolophidae), Sudis hyalina Rafinesque, 1810 (Osteicthyes: Paralepididae), Brama brama (Bonnaterre, 1788) (Osteichthyes: Bramidae) and Trachipterus trachypterus (Gmelin, 1789) (Osteichthyes: Trachipteridae) were recorded for the first time in the Eastern Ionian Sea. The absence of these new or rare species from the ichthyofauna of the study area to date is probably related to the absence of adequate sampling and catching techniques, although environmental factors could also be involved. 相似文献
345.
We consider dynamic capacity booking problems faced by multiple manufacturers each outsourcing certain operations to a common third-party firm. Each manufacturer, upon observing the current state of the third-party schedule, books capacity with the objective to jointly minimize holding costs that result from early deliveries, tardiness penalties due to late deliveries, and third-party capacity booking costs. When making a reservation, each manufacturer evaluates two alternative courses of action: (i) reserving capacity not yet utilized by other manufactures who booked earlier; or (ii) forming a coalition with a subset or all of other manufacturers to achieve a schedule minimizing coalition costs, i.e., a centralized schedule for that coalition. The latter practice surely benefits the coalition as a whole; however, some manufacturers may incur higher costs if their operations are either pushed back too much, or delivered too early. For this reason, a cost allocation scheme making each manufacturer no worse than they would be when acting differently (i.e., participating in a smaller coalition or acting on their own behalf,) must accompany centralized scheduling for the coalition. We model this relationship among the manufacturers as a cooperative game with transferable utility, and present optimal and/or heuristic algorithms to attain individually and eoalitionally optimal schedules as well as a linear program formulation to find a core allocation of the manufacturers' costs. 相似文献
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Serguei V. Triapitsyn Chrysalyn Dominguez John T. Huber George Japoshvili John M. Heraty 《Journal of Natural History》2020,54(9-12):585-596
ABSTRACT Based on morphological and molecular evidence, the European fairyfly Herulia sundholmi Hedqvist syn. n. (Hymenoptera: Mymaridae) is removed from previous synonymy with the Nearctic Macrocamptoptera metotarsa (Girault), and synonymised with the Palaearctic M. grangeri Soyka, which is newly recorded from Georgia, Slovakia and Spain. Macrocamptoptera bulagarica (Donev) syn. n., known from Bulgaria and Italy, is also synonymised with M. grangeri. An updated key to females of the three currently recognised species of the rarely collected genus Macrocamptoptera Girault is given. 相似文献
348.
Networked control systems are subject to adversary conditions that affect their network topologies. To ensure reliable system operations, network topologies need to be characterized and managed for their impact on the overall system performance. This paper introduces the concept of network robustness depth for this pursuit. Discrete event systems are used as a foundation to model dynamic behavior of network topologies, support their analysis, and carry out their management. Stochastic analysis relates the link reliability probabilities to a probabilistic characterization of network robustness depth. Several topology management strategies are discussed, including passive methods, random strategies, and optimization methodologies. Their respective benefits and limitations are quantified. By using platoon control as a platform of hybrid (continuous and discrete event) systems and packet erasure channels as a communication protocol, the results are demonstrated with case studies. 相似文献
349.
R. George H.-L. Chan Z. Ahmed K. M. Suen C. N. Stevens J. A. Levitt K. Suhling J. Timms J. E. Ladbury 《Cellular and molecular life sciences : CMLS》2009,66(4):711-720
The three isoforms of the adaptor protein Shc play diverse roles in cell signalling. For example, the observation of p46 Shc
in the nuclei of hepatocellular carcinoma cells suggests a function quite distinct from the better characterised cytoplasmic
role. Ligands responsible for the transport of various Shc isoforms into organelles such as the nucleus have yet to be reported.
To identify such ligands a far western approach was used to determine the p52 Shc interactome. The Ran-GTPase nuclear transport
protein was identified and found to bind to p52 Shc in vitro with low micromolar affinity. Co-immunoprecipitation, pull down and fluorescence lifetime imaging microscopy experiments
in stable cells confirmed cellular interaction and nuclear localisation. The nuclear transport factor protein NTF2, which
functions in cohort with Ran, was shown to form a complex with both RAN and Shc, suggesting a mechanism for Shc entry into
the nucleus as part of a tertiary complex.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Received 20 October 2008; received after revision 04 December 2008; accepted 15 December 2008 相似文献
350.
McKay JD Hung RJ Gaborieau V Boffetta P Chabrier A Byrnes G Zaridze D Mukeria A Szeszenia-Dabrowska N Lissowska J Rudnai P Fabianova E Mates D Bencko V Foretova L Janout V McLaughlin J Shepherd F Montpetit A Narod S Krokan HE Skorpen F Elvestad MB Vatten L Njølstad I Axelsson T Chen C Goodman G Barnett M Loomis MM Lubiñski J Matyjasik J Lener M Oszutowska D Field J Liloglou T Xinarianos G Cassidy A;EPIC Study Vineis P Clavel-Chapelon F Palli D Tumino R Krogh V Panico S González CA 《Nature genetics》2008,40(12):1404-1406
We carried out a genome-wide association study of lung cancer (3,259 cases and 4,159 controls), followed by replication in 2,899 cases and 5,573 controls. Two uncorrelated disease markers at 5p15.33, rs402710 and rs2736100 were detected by the genome-wide data (P = 2 x 10(-7) and P = 4 x 10(-6)) and replicated by the independent study series (P = 7 x 10(-5) and P = 0.016). The susceptibility region contains two genes, TERT and CLPTM1L, suggesting that one or both may have a role in lung cancer etiology. 相似文献