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In the parable of Simon's Ant, an ant follows a complex path along a beach on to reach its goal. The story shows how the interaction of simple rules and a complex environment result in complex behavior. But this relationship can be looked at in another way - given path and rules, we can infer the environment. With a large population of agents - human or animal - it should be possible to build a detailed map of a population's social and physical environment. In this abstract, we describe the development of a framework to create such maps of human belief space. These maps are built from the combined trajectories of a large number of agents. Currently, these maps are built using multidimensional agent-based simulation, but the framework is designed to work using data from computer-mediated human communication. Maps incorporating human data should support visualization and navigation of the "plains of research", "fashionable foothills" and "conspiracy cliffs" of human belief spaces.

Summary Ants can modify the properties of soil when they build their nests. We have investigated the degree and persistency of changes of soil morphology and chemistry in abandoned anthills in a temperate, deciduous wood in Jutland, Denmark. For this purpose, we sampled surface soils (0–10 cm) from each of five abandoned anthills ( Formica polyctena Förster) and adjacent undisturbed sites, where anthills covered about 0.5% of the surface area. In addition, one soil profile in an abandoned anthill was sampled for morphological descriptions. All samples were analysed for pH, C, N, lignin‐derived phenol, and cellulosic and non‐cellulosic carbohydrate concentrations. The results showed that soils under the anthills were enriched in organic matter, were yellower and showed features of Podzol degradation. Former Podzols had to be reclassified to Umbrisols or Arenosols, whereas anthills on Luvisols affected soil classification only at the subdivision level. The C/N ratio and soil pH were not significantly affected by the ants' activity. However, lignin‐derived phenols and cellulosic polysaccharides were enriched inside the mounds by a factor of 6 and 7, respectively. This probably reflected collection of woody debris for nest construction while the nest was occupied, and large input of C from an increased root density. The degree of changes in the quality of the organic matter decreased with time since abandonment, but changes were still detectable within anthills left 20 years ago. As ant colonies are concentrated, and move regularly on a decadal timescale, formation of Formica anthills has an intrinsic influence on the heterogeneity of the soil within this forest ecosystem.

The removal of methylene blue (MB) dye and hexavalent chromium (Cr(Vl)) ions from water bodies have necessitated the search for a promising adsorbent material with high adsorptive performance, facile operation, and economical. Here, a novel adsorbent was prepared by activating anthill clay (AC) with Ocimum gratissimum leaf extract (OG@AC) by ultrasonic strategy method to eliminate MB and Cr(Vl) from the aqueous environment; however, the activation strategy serves as an important factor that influenced the adsorptive performance towards MB and Cr(Vl). Furthermore, a high BET surface area of 120.48 m 2 /g was measured for OG@AC which is attributed majorly to the green activation strategy. The SEM micrograph of OG@AC was seen to have displayed a leaf-like plate formed by quartz and kaolin. In the batch experimental study, the MB and Cr(Vl) adsorption capacities towards OG@AC were determined to be 227.52 and 143.45 mg/g, respectively. Also, the adsorption kinetics and isotherms models results revealed that the adsorption process of OG@AC towards MB and Cr(Vl) was best described by pseudo-first-order and Freundlich models, suggesting that the adsorption process involves a multilayer physisorption. Moreso, thermodynamic results revealed the adsorption process is feasible, spontaneous, and endothermic in nature. The OG@AC exhibited an outstanding regeneration ability and stability towards MB and Cr(Vl) by maintaining a removal efficiency of 79.11 % and 81.20 % even at the tenth successive adsorption-desorption cycles. Overall, this research sheds more insight on how anthill clay is activated using a feasible design and green chemical ( Ocimum gratissimum leaf extract) to enhance its adsorptive performance towards MB and Cr(Vl), which can broaden its wide application in the real world. • Enhanced OG@AC was developed for MB and Cr(Vl) adsorption. • OG@AC) exhibited an improved BET surface area of 120.48 m2/g. • OG@AC adsorption capacity reached 227.52 and 143.45 mg/g for MB and Cr(Vl). • OG@AC exhibits excellent stability (>75 %) after ten adsorption-desorption cycles.

Knowledge and Power, the Story and the Storyteller:Achebe's Anthills of the Savannah Robin Ikegami (bio) Many critical discussions of Chinua Achebe as storyteller center on the ways in which he deliberately draws upon an African oral tradition to enhance his efforts to depict different tensions—such as that between precolonial Ibo ways of thinking and Christian missionary notions, or between men and women, or between generations. Such critics point to Achebe's use of proverbs, different speech rhythms, and repetition,1 but they do not explicitly address in any detail the role of storytelling itself as a political or social act—as a demonstration of knowledge and an exercise of power—within the novels. Although each of Achebe's five novels demonstrates his own power as a storyteller and reveals his view of the complex and often problematic relation between knowledge, power, and storytelling, nowhere does Achebe more minutely examine the nature of that relation than in his latest novel, Anthills of the Savannah (1987). My endeavor in this paper is to examine both Achebe's storytelling and his view of the act of storytelling as manifested in his most recent novel to determine the ways in which power and knowledge impinge upon stories and their tellers. [End Page 493] Unlike his previous novels, Anthills features characters who are concerned neither with negotiating a way between black society and white government (as in Things Fall Apart, No Longer at Ease, and Arrow of God) nor with making a direct transition from colonialism to self-government (as in Man of the People); instead, these characters are occupied with finding a way of establishing and maintaining a successful form of postcolonial self-government. Rather than trying to fill in the skeletal structure of government left by colonialism, they attempt to construct a new government out of their history, a contemporary African government. The relation between knowledge and power in Anthills, then, is particularly problematic, for the characters have a great deal of various kinds of knowledge, and they believe that they have a certain amount of power as well. But they recognize that the possession of that knowledge and power is not necessarily enough to ensure either their own well-being and survival or those of their society.2 They are almost perpetually in a state of confusion because the extent of their knowledge and power is always in question, not only in their own minds but in the minds of others as well. Thus the trope of storytelling and Achebe's own storytelling also demonstrate that confusion.3 Each of the main characters—Chris, Ikem, the president, and Beatrice—participates in the storytelling. Unlike the stories we find in the earlier novels, these stories are not seen as sources of solutions to problems; no one views them as coherent wholes that offer reassurance or advice. The stories in Anthills only suggest more questions for the characters. Thus the concept of knowledge is problematized; what makes for knowledge, how it is acquired, how it is or should be used—all are questions with which the characters, and Achebe himself, struggle throughout the novel. Significantly, the limits and complexities of the power of storytelling and storytellers in Anthills may be, at least in part, attributed to the historical setting of the novel.4 The book's characters represent a generation [End Page 494] of Africans that has never experienced life without numerous uncertainties; unlike the characters in the earlier novels, the main characters in Anthills have not maintained close connections with a traditionally ordered society. Significantly, Anthills takes place during a time when colonialism is neither an impending threat nor a concrete presence; rather, colonialism is something of a haunting but distant memory, the remnant of a past the novel's leading characters would like to transcend but which has in some overt as well as covert ways influenced the concept of government current through most of the novel. But the early forms of precolonial government are also only a vague memory, like colonialism, influencing although not dominating newer constructions of institutional power. The characters know about the overthrow of different institutions of power, and consequently, they realize that power is...

Ants are known to concentrate phosphorus (P) inside their nests via collection of food and litter. To elucidate the possible effects on long-term availability of soil P, five anthills abandoned by Red wood ant (Formica polyctena Förster) > 5—20 years ago were characterized for soil P forms in a temperate Danish deciduous forest. Sequentially extracted P fractions and liquid-state 31P nuclear magnetic resonance (NMR) spectra were obtained on surface samples (0—10 cm) from abandoned anthills and adjacent topsoil; in addition one representative soil profile in an abandoned anthill was investigated. The results show that different inorganic and all organic P fractions were enriched by a factor of 2.0—3.3 inside anthills relative to the surrounding soil. The soil underneath the abandoned anthill had higher P contents until 50-cm depth. Phosphorus composition was less affected by former anthill construction. Only the younger anthills revealed a preferential accumulation of labile organic P forms such as Na-HCO3 extractable P or diester P. The accumulation of the stable and moderate labile P forms, however, persisted for ≥ 20 years after abandonment. We concluded that former ant activity enhanced long-term P availability of soil due to high local P inputs, whereas changes of the P form distribution lasted 5—10 years after nest abandonment.

Contradictions and Alternatives in Chinua Achebe's Anthills of the Savannah Ali Erritouni, Senior lecturer in American literature I. Chinua Achebe's Anthills of the Savannah (1987) exposes the ills of the African postcolonial nation-state in an effort to propose credible alternatives to them. These alternatives are best described as horizons because they do not take the form of systematic solutions or detailed political and social programs. In Anthills we find a groping for possibilities that are largely fragmentary, undecided—often amorphous. Its approach to the question of the nation-state is, moreover, marked by a deep ambivalence. This ambivalence, I will argue, should not be construed as the result of the author's inability to come to terms with the implications of his contradictory views (as David A. Maughan Brown believes) but instead reflects inherent tensions that characterize the postcolonial nation-state and the available alternatives that may remedy its abuses. With the critique Achebe mounts against the nation-state in Anthills, he attempts to clear a space that will enable fresh possibilities and open new horizons. Some of the new possibilities he suggests capture the political alternatives that Africans have put forward to redress the failure of many African nation-states to fulfill their peoples' aspirations. In so doing, Achebe represents the contemporary political situation in its irreducible complexity, refusing to resolve the contradictions that necessarily obtain from such a painstaking representation. Achebe assigns enlightened intellectuals a significant role in imagining alternatives to the nation-state. He holds that an enlightened leadership of intellectuals, represented in Anthills notably by Chris Oriko and Ikem Osodi, could be instrumental in leading Nigerians and Africans beyond the impasses of their [End Page 50] nation-states. He also proposes the emulation of indigenous forms of government, which valorize plural decision-making and horizontal power relations. This return to pre-colonial societies for the political lessons they can afford may appear atavistic and reactionary, but in Achebe's hands they hold up a mirror to the nation-state, not only to further undermine its legitimacy, but to compete with it for political significance. Alongside enlightened intellectuals and the horizontal political institutions of traditional societies, Achebe dramatizes a woman, Beatrice Okoh, in positions of leadership, something that nationalism has disregarded and that postcolonial intellectuals have started to consider seriously. The novel concludes with a small multi-ethnic, multi-linguistic, and religiously diverse group, which offers some utopian possibilities. In a 1987 interview with Anne Rutherford, Achebe rehearses these distinct alternatives, revealing in the process the contradictions they sustain. He asserts that the way out of the morass of the Nigerian nation-state lies in "the few thinking people," "leaders," "elite," "greatness," "a handful of people" (2–3). "[T]o correct the situation" (2), the elite must "create the circumstances in which the people begin to act with awareness" (3) and must use their special "training and education and qualifications . . . to initiate the upward movement of the people" (5). According to this view, the people lack initiative, insight to lead themselves, and the ability to think of alternatives, as they don't naturally belong to "the few thinking people." However, almost in the same breath, Achebe contradicts this view by asserting that it is through ordinary people, being "the owners of the country" (5), that a new world will be born. As Brown points out, "The logic of Achebe's fixation on 'leadership', as embodied in [Anthills], would lead not to democracy but to enlightened dictatorship by the elite—an outcome somewhat at odds with the populist tendency of Achebe's views" (21). In the same interview, Achebe regrets the exclusion of women from politics, both in society and in his novels, and contends that he has sought to remedy such neglect in Anthills. To this end, he informs us that he has elevated the main female character, Beatrice, to the level of enlightened leader: We have created all kinds of myths to support the suppression of the woman . . . I am saying the woman herself will be in the forefront in designing what her new role is going to be, with the humble cooperation of men. The position of Beatrice as sensitive leader . . . is...

Background and Objective: The generation of wastewater containing heavy metals has become an issue as their release into the environment has increased as a result of industrialization. This wastewater contains amounts of heavy metals that are harmful to human beings and aquatic species. This present study was aimed to develop mixed anthill-chicken eggshell as composite adsorbent and use to remove heavy metals contained in an aqueous solution via adsorption process. Materials and Methods: The stock solution was prepared by dissolving desired amount of Cu(II) and Zn(II) nitrate in a known volume of deionized water. After preparation of anthill and eggshell powders, the mixed anthill-eggshell preparation conditions were optimized by maximizing the heavy metals uptakes using Central Composite Design (CCD) of response surface methodology (RSM) in design expert 7.0.0 as an optimization tool. The fitness of the developed models was evaluated by analysis of variance (ANOVA-Type III). Results: Findings revealed that the predicted Cu(II) and Zn(II) ions uptakes from the two suggested models agreed reasonably well with the experimental values. The obtained data showed that at 863.78EC calcination temperature, 4 h calcination time and eggshell/anthill mixing ratio of 1.86, the percentages of Cu(II) and Zn(II) ions removed from aqueous solution by optimal composite anthill-eggshell adsorbent were 97.89 and 99.34% respectively. Conclusion: The analyses results revealed that composite anthill-eggshell adsorbent was porous, possessed active functional groups on its surface and made up of active mixed metal oxides with close interaction.

Recent peer-to-peer (P2P) systems are characterized by decentralized control, large scale and extreme dynamism of their operating environment. As such, they can be seen as instances of complex adaptive systems (CAS) typically found in biological and social sciences. We describe Anthill, a framework to support the design, implementation and evaluation of P2P applications based on ideas such as multi-agent and evolutionary programming borrowed from CAS. An Anthill system consists of a dynamic network of peer nodes; societies of adaptive agents travel through this network, interacting with nodes and cooperating with other agents in order to solve complex problems. Anthill can be used to construct different classes of P2P services that exhibit resilience, adaptation and self-organization properties. We also describe preliminary experiences with Anthill in implementing a file sharing application.

A heterogeneous catalyst was developed from raw Kwale red Anthill mud by thermal treatment in a muffle furnace at 900 °C for 4 h. The resulting heterogeneous catalyst was highly porous with a surface area of 42.16m 2 /g, possessing excellent stability as well as high catalytic activity. Central Composite Design and Machine Learning approach (Python code) were applied to model and optimize biodiesel yield from extracted watermelon oilseed. Highest biodiesel yield of 93.41 wt% was obtained under the experimental conditions of 4min duration, 350 W microwave power, 4 wt% of catalyst, and MeOH/oil ratio of 8:1 based on Central Composite Design rotatable. The optimum value of the biodiesel yield from Machine Learning was 91.7 wt%, showing a marginal performance over the Central Composite Design rotatable value (91.6 wt%) at the optimized conditions of 3 min, 280 W, 3 wt% catalyst loading and MeOH/oil molar ratio of 6:1. The correlation of the coefficient (R 2 ) of the model was 0.9827 for Central Composite Design rotatable while the R 2 of the Machine Learning model was 1.0. Thus, python coding in terms of prediction and accuracy of biodiesel yield was superior to Central Composite Design rotatable, even though both models provide a reliable response within the region of data analyzed. The Gas Chromatography-Mass Spectroscopy of the biodiesel produced revealed the presence of both saturated and unsaturated fatty acid methyl esters. Biodiesel properties from watermelon seed oil transesterification fall within the recommended standard for biodiesel fuel. This study concluded that an effective green biowaste catalyst generated from earthen waste could enhance biodiesel production from watermelon seed oil, hence, ensuring sustainability and economic feasibility for biodiesel industries.