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Tarik Hadzibeganovic Francisco W. S. Lima Dietrich Stauffer 《Behavioral ecology and sociobiology》2014,68(7):1059-1072
We study the effects of working memory capacity and network rewiring probability on the evolution of cooperation in the standard and modified versions of an agent-based model of tag-mediated altruism. In our evolutionary model, computational agents populate a large complex network, engage into multiplayer Prisoner’s Dilemma-like interactions, and reproduce sexually. Agents carry discernible phenotypic traits subject to mutation, memorize their own experiences, and employ different strategies when interacting with different types of co-players. Choices made are selected from a pool of two conditional and two unconditional strategies, depending on the available memory contents and phenotypic similarity among interactors. For the dominating strategy in our standard model version, we found a strong dependence of cooperation on network structure and a weak one on memory, whereas in the modified version, the structural effect was weaker than that of memory. Most importantly, we found that the previously reported decline of cooperation in memory-based models, typically observed at a high memory capacity, is now prevented with the help of tags. This suggests that the evolutionary advantages of memory capacity limits may be far more complex than previously assumed. For much smaller systems, we observed a quasi-symmetric alternation of the two winning groups of strategists. This result provides an example of ingroup biased interactions that are characterized by bursts of intra-tag cooperation interspersed with periods of unconditional transient altruism. Such switches of strategies may represent a boosting mechanism necessary for the emergence and stability of global altruism in its early evolutionary stages. 相似文献
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In marine systems, the occurrence and implications of disturbance-recovery cycles have been revealed at the landscape level, but only in demographically open or closed systems where landscape-level dynamics are assumed to have no feedback effect on regional dynamics. We present a mussel metapopulation model to elucidate the role of landscape-level disturbance cycles for regional response of mussel populations to onshore productivity and larval transport. Landscape dynamics are generated through spatially explicit rules, and each landscape is connected to its neighbor through unidirectional larval dispersal. The role of landscape disturbance cycles in the regional system behavior is elucidated (1) in demographically open vs. demographically coupled systems, in relation to (2) onshore reproductive output and (3) the temporal scale of landscape disturbance dynamics. By controlling for spatial structure at the landscape and metapopulation levels, we first demonstrate the interaction between landscape and oceanographic connectivity. The temporal scale of disturbance cycles, as controlled by mussel colonization rate, plays a critical role in the regional behavior of the system. Indeed, fast disturbance cycles are responsible for regional synchrony in relation to onshore reproductive output. Slow disturbance cycles, however, lead to increased robustness to changes in productivity and to demographic coupling. These testable predictions indicate that the occurrence and temporal scale of local disturbance-recovery dynamics can drive large-scale variability in demographically open systems, and the response of metapopulations to changes in nearshore productivity. 相似文献
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Mohamed Hanine Omar Boutkhoum Abderrafie El Maknissi Abdessadek Tikniouine Tarik Agouti 《The Environmentalist》2016,36(4):351-367
The location selection for landfill municipal solid waste is an important issue in waste management. Selection of the optimal location requires consideration of multiple alternative solutions and evaluation factors because of system complexity. Further, ranking of the alternative locations and selection of the most optimal and efficient locations for landfill waste are an important multi-criteria decision-making problem. In this study, the candidate locations for landfill are determined based on Political, Economical, Environmental and Social factors are assessed through decision-makers’ opinion and by the methodology that incorporates fuzzy analytic hierarchy process (fuzzy AHP) and fuzzy technique for order preference by similarity to ideal solution (fuzzy TOPSIS). Specifically, the fuzzy AHP technique is applied to determine the weights of selected criteria impacting the location selection process, and the fuzzy AHP is adapted to model the linguistic vagueness and ambiguity, which can also be expressed as triangular fuzzy numbers. Furthermore, fuzzy TOPSIS technique is employed to rank the alternative locations. The applicability of this methodology is demonstrated by a case study of landfill waste location selection in the region of Casablanca, Morocco, and the results are compared with other techniques. Finally, to complete the treatment, a sensitivity analysis is performed to examine the impact of the preferences given by decision-makers to choose the best location. 相似文献
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T. Meziane S. Y. Lee P. L. Mfilinge P. K. S. Shin M. H. W. Lam M. Tsuchiya 《Marine Biology》2007,150(6):1103-1113
Fatty acid compositions of the leaves of six species of mangroves were studied to ascertain their use as biomarkers for determining
the fate of mangrove organic matter in the habitat and as taxonomic tool. Mangrove leaves were collected from three locations
in the western Pacific Ocean: Moreton Bay (MB) (Australia), Hong Kong (China) and Okinawa (Japan). In MB, samples were collected
from two sites separated by 15 km: Logan River Estuary (LRE) and Jabiru Island. In addition, along the LRE, leaves were collected
from five stations at ∼2–3 km apart. Results show that the analysis of the entire fatty acid profiles of the mangrove leaves
is a promising taxonomic tool as the profiles of most species were sufficiently different to be separated in an non-metric
multidimensional scaling plot. In addition, geographically separated populations of the same species could also be identified
by their fatty acid profiles. In most cases, two non-ubiquitous groups of fatty acids dominated in the mangrove leaves: the
polyunsaturated 18:2ω6 and 18:3ω3 and the long chain fatty acids (≥24:0). With respect to the relative contributions of these
fatty acids, three groups of species were identified, in which one or both groups of fatty acids may potentially be used as
markers of the mangrove organic matter in the estuarine environment. 相似文献
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Sanda Midžić-Kurtagić Irem Silajdžić Tarik Kupusović 《Journal of Cleaner Production》2010,18(15):1535-1544
The objective of this paper is to discuss the mapping methodology implemented in the selection of BAT candidates and to present the results of the mapping of B&H food and beverage sector, prepared as a baseline for the development of national reference documents on Best Available Techniques. The subsectors subject to analysis were: dairy, fish farming, fish processing, fruit and vegetable processing, meat processing, breweries, and slaughterhouses.The sector was mapped from several aspects, including socio-economic, legal, and environmental point of view. The socio-economic aspect focused on understanding the sector’s structure and financial capabilities, pricing for water, energy, and solid waste consumption, as well as employee profiles, in order to better assess the sustainability of decisions taken. Legal mapping focused on relevant regulations, including policies from the following sectors: environment, water use and protection, food safety, agriculture, and veterinary, in order to determine legal requirements from an environmental protection aspect set in the various sector policies. Environmental performance indicators were calculated in order to assess present resource efficiencies and relevant environmental impacts. In addition, the mapping process also addressed the existing level of BAT implementation in the subsectors under consideration.The paper presents a rationale for methodology selection, offers a review of the mapping methodology used, discusses mapping results and provides conclusions in regards to that methodology used and discusses issues that need to be considered in the selection of BAT candidates. 相似文献
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Kerambrun E Le Floch S Sanchez W Thomas Guyon H Meziane T Henry F Amara R 《Chemosphere》2012,87(7):692-702
In the present study, juvenile sea bass were exposed for 48 and 96 h to an Arabian light crude oil and their responses were assessed at the molecular and physiological levels. The aim of the study was therefore to assess (i) the short term effects of crude oil exposure by the measurement of several molecular biomarkers, (ii) the consequences of this short term exposure on fish health by using growth and condition indices measured after a decontamination period of 28 and 26 d in seawater. Hydrocarbon petroleum concentrations was monitored during the 96 h experiments and an increase of PAH concentrations were found in fish following both exposure times. An 7-ethoxyresorufin-O-deethylase (EROD) induction was observed after 48 h of exposure, while a significant decrease in the sea bass specific growth rate in length and for the RNA:DNA ratio was observed 28 d after that exposure ceased. The EROD induction doubled after the 96 h exposure, and a significant increase in GST activities was observed. A significant decrease in the specific growth rates, the otolith recent growth, the RNA:DNA ratio and the Fulton’s K condition index were then observed in sea bass 26 d after the 96 h exposure to mechanically dispersed crude oil compared to the control. The present study shows that growth and condition indices can prove useful in assessing fish health status following an oil spill. Their complementary analysis with sensitive molecular biomarkers as EROD could improve the determination of oil spill impact on fish populations. 相似文献
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Caroline Nerot Tarik Meziane Anais Provost-Govrich Hervé Rybarczyk S. Yip Lee 《Marine Biology》2009,156(11):2343-2352
The influence of the crab Parasesarma erythrodactyla on the entry of the organic matter derived from Avicennia marina mangrove leaves in a sub-tropical mangrove ecosystem of southeast Queensland, Australia, was simulated using tidal mesocosms.
Degradation of mangrove leaf organic matter was followed by analysing the fatty acid composition, carbon, and nitrogen isotopic
signatures of the surface sediment and suspended particulate organic matter (SPOM) with and without the presence of crabs.
Assimilation of mangrove organic matter by P. erythrodactyla was also assessed by stable isotope and fatty acid analyses in tissues and faeces. Results of the chemical tracer analyses
question the adaptability of P. erythrodactyla to a diet comprised exclusively of mangrove leaves, and suggest that these organisms were dependent on additional food sources
in their natural environment. Crab processing of senescent leaves significantly accelerated the transfer of mangrove organic
matter to the surface sediments, as shown by a higher C/N ratio, a higher contribution of long-chain fatty acids and a more
depleted C isotopic signature of sediment samples in the mesocosms with crabs compared to those without crabs. 相似文献
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Zarrouk Tarik Salhi Jamal-Eddine Atlati Samir Nouari Mohammed Salhi Merzouki Salhi Najim 《Environmental science and pollution research international》2022,29(1):98-105
Environmental Science and Pollution Research - The machining of Nomex honeycomb structures represents a technical and scientific barrier for aeronautical applications. The difficulties encountered... 相似文献
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