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991.
Cecilia Polacow Herzog 《Landscape and Ecological Engineering》2016,12(1):141-150
The city of Rio de Janeiro now covers what was formerly coastal Atlantic rainforest. Native biodiversity has been lost from most of the metropolitan area due to changes in land use, introduction of exotic species, and influence of foreign designs in public and private parks and gardens. This paper presents a multifunctional green infrastructure planning proposal to protect and regenerate native biodiversity in the last remaining natural ecosystem fragments in a watershed within the city’s limits. The proposal is based on social–ecological assessments and analyses. The watershed contains an extensive mangrove remnant surrounded by a protected massif partially covered by coastal Atlantic rainforest and is one of the very last productive landscapes where residents experience a strong sense of place. The strategy is to reconcile urban development with environmental achievements to conserve existing ecosystem patches, which will be connected by way of riparian corridors and other open spaces, such as streets, private yards and public areas, by using native species and ecological design. The green infrastructure framework is planned at the watershed scale. On a neighborhood and local scale, the plan is to promote public participation, develop new ecological aesthetics, encourage the planting of native species, and establish an innovative circulation system within a low-impact design framework to achieve various abiotic, biotic, and cultural goals. In addition to the economic benefits, accessible food production, rural tourism and ecotourism have the potential to unite people and nature within the city. 相似文献
992.
993.
Jared C. Foster Bin Nan Lei Shen Niko Kaciroti Jeremy M. G. Taylor 《Statistics in biosciences》2016,8(1):77-98
We consider the problem of using permutation-based methods to test for treatment–covariate interactions from randomized clinical trial data. Testing for interactions is common in the field of personalized medicine, as subgroups with enhanced treatment effects arise when treatment-by-covariate interactions exist. Asymptotic tests can often be performed for simple models, but in many cases, more complex methods are used to identify subgroups, and non-standard test statistics proposed, and asymptotic results may be difficult to obtain. In such cases, it is natural to consider permutation-based tests, which shuffle selected parts of the data in order to remove one or more associations of interest; however, in the case of interactions, it is generally not possible to remove only the associations of interest by simple permutations of the data. We propose a number of alternative permutation-based methods, designed to remove only the associations of interest, but preserving other associations. These methods estimate the interaction term in a model, then create data that “looks like” the original data except that the interaction term has been permuted. The proposed methods are shown to outperform traditional permutation methods in a simulation study. In addition, the proposed methods are illustrated using data from a randomized clinical trial of patients with hypertension. 相似文献
994.
Can the activities of the large scale cortical network be expressed by neural energy? A brief review
This paper mainly discusses and summarize that the changes of biological energy in the brain can be expressed by the biophysical energy we constructed. Different from the electrochemical energy, the biophysical energy proposed in the paper not only can be used to simulate the activity of neurons but also be used to simulate the neural activity of large scale cortical networks, so that the scientific nature of the neural energy coding was discussed. 相似文献
995.
Pollination is a crucial plant–animal interaction in ecosystems, and moths (Lepidoptera) are a widespread and species-rich group of flower visitors. In this article, plant and moth species connected via pollination interactions were identified from the literature, and information on the relevance of moth pollination in various ecosystems, including agro-ecosystems, was compiled, particularly for Europe and North America. Overall, 227 moth–flower pollination interactions were found, including certain specialized relationships between plants and pollinating seed predators. Most of the interactions could be attributed to the moth families Noctuidae (90 interactions, 56 species) and Sphingidae (85 interactions, 32 species), and to the plant families Orchidaceae (109 interactions, 22 species) and Caryophyllaceae (59 interactions, 16 species). Limited information is available on the role of moth pollination in natural ecosystems (7 studies). In temperate agro-ecosystems, moths are most likely not essential to crop pollination, but they can contribute to the pollination of non-crop plants, which are crucial to maintaining biodiversity in these ecosystems. In general, the role of moths as pollinators appears to be underestimated because only a few studies on moth pollination are available, and long-term, ecosystem-scale research is necessary to address temporal fluctuations in their abundance and community composition. 相似文献
996.
Sergio Rodríguez 《Biosemiotics》2016,9(2):169-184
This article addresses the semiotic problem of how meaning is agentially grounded: how actual meaning is possible and is justifiably supported by agents’ capabilities and purposes. This article is particularly focused on human agential grounding; however, to a great degree, insights presented here can be extended to other living beings. Specifically, agential meaning is examined here inside the framework of agentive semiotics and embodied, situated and enactive cognition theories, in line with the mind-life continuity general thesis (which intends to naturalize mind and experience). To offer clarity and methodological precision about agential grounding, three explanation categories (called recurrences) are proposed: phylogenetic recurrence, the evolutionary basis for corporal/embodied grounding; ontogenetic recurrence, the developmental basis for individual meaning grounding; and collective recurrence, the basis for meaning recognized, attributed and assigned inside social contexts. These recurrences are conceived as three types of general processes that constantly enclose possibilities for purpose and meaning emergence in humans. As a result of these types of recurrences, two categories of human agendas or purposes are also proposed: individual and collective. Finally, remarks about how these categories can be useful for semiotic analysis and further research are suggested. 相似文献
997.
998.
Turtles are among the most intriguing amniotes but their communication and signaling have rarely been studied. Traditionally, they have been seen as basically just silent armored ‘walking stones’ with complex physiology but no altruism, maternal care, or aesthetic perception. Recently, however, we have witnessed a radical change in the perception of turtle behavioral and cognitive skills. In our study, we start by reviewing some recent findings pertaining to various highly developed behavioral and cognitive patterns with special emphasis on turtles. Then we focus on freshwater turtles and use data about their sexual behavior and size sexual dimorphism (SSD) to test whether conspicuous coloration of the head is in these animals related to sexual processes. We found that absence of aggressive mating behavior is statistically associated with the presence of conspicuous coloration on turtles’ heads. It also seems that while species with female-biased SSD are characterised by conspicuously colored head ornaments, in species with male-biased SSD conspicuous coloration is absent. Unlike large females, males thus seem to be under pressure to develop conspicuous coloration and engage in non-aggressive behavior using signaling to succeed in courtship. And finally, we discuss possible roles of head color patterns in turtle communication during mating. 相似文献
999.
Understanding the dynamics of ecological systems using stability concepts has been a key driver in ecological research from the inception of the field. Despite the tremendous effort put into this area, progress has been limited due to the bewildering number of metrics used to describe ecological stability. Here, we seek to resolve some of the confusion by unfolding the dynamics of a simple consumer-resource interaction module. In what follows, we first review common dynamical metrics of stability (CV, eigenvalues). We argue using the classical type II consumer-resource model as an example where the empirical stability metric, CV, hides two different, but important, aspects of stability: (i) stability due to mean population density processes and (ii) stability due to population density variance processes. We then employ a simple stochastic consumer-resource framework in order to elucidate (i) when we expect these two different aspects of stability to arise in ecological systems and, importantly, highlight (ii) the fact that these two different aspects of stability respond differentially, but predictably, to changes in fundamental parameters that govern biomass flux and loss in any consumer-resource interaction (e.g., attack rates, carrying capacity, mortality). 相似文献
1000.
Alexey Pimashkin Arseniy Gladkov Ekaterina Agrba Irina Mukhina Victor Kazantsev 《Cognitive neurodynamics》2016,10(4):287-299
Sensory information can be encoded using the average firing rate and spike occurrence times in neuronal network responses to external stimuli. Decoding or retrieving stimulus characteristics from the response pattern generally implies that the corresponding neural network has a selective response to various input signals. The role of various spiking activity characteristics (e.g., spike rate and precise spike timing) for basic information processing was widely investigated on the level of neural populations but gave inconsistent evidence for particular mechanisms. Multisite electrophysiology of cultured neural networks grown on microelectrode arrays is a recently developed tool and currently an active research area. In this study, we analyzed the stimulus responses represented by network-wide bursts evoked from various spatial locations (electrodes). We found that the response characteristics, such as the burst initiation time and the spike rate, can be used to retrieve information about the stimulus location. The best selectivity in the response spiking pattern could be found for a small subpopulation of neurones (electrodes) at relatively short post-stimulus intervals. Such intervals were unique for each culture due to the non-uniform organization of the functional connectivity in the network during spontaneous development. 相似文献