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It is a recurring requirement in open systems, such as networks, distributed systems, and socio-technical systems, that a group of agents must coordinate their behaviour for the common good. In those systems—where agents are heterogeneous—unexpected behaviour can occur due to errors or malice. Agents whose practices free-ride the system can be accepted to a certain level; however, not only do they put the stability of the system at risk, but they also compromise the agents that behave according to the system’s rules. In social systems, it has been observed that social capital is an attribute of individuals that enhances their ability to solve collective action problems. Sociologists have studied collective action through human societies and observed that social capital plays an important role in maintaining communities though time as well as in simplifying the decision-making in them. In this work, we explore the use of Electronic Social Capital for optimising self-organised collective action. We developed a context-independent Electronic Social Capital framework to test this hypothesis. The framework comprises a set of handlers that capture events from the system and update three different forms of social capital: trustworthiness, networks, and institutions. Later, a set of metrics are generated by the forms of social capital and used for decision-making. The framework was tested in different scenarios such as two-player games, n -player games, and public goods games. The experimental results show that social capital optimises the outcomes (in terms of long-term satisfaction and utility), reduces the complexity of decision-making, and scales with the size of the population. This work proposes an alternative solution using Electronic Social Capital to represent and reason with qualitative, instead of traditional quantitative, values. This solution could be embedded into socio-technical systems to incentivise collective action without commodifying the resources or actions in the system.

A self-governing institution designed according to Ostrom's principles provides a way for its members to self-organise the management and sustainability of common-pool resources. Such institutions have been studied as a form of social capital, used as an input to a decision-making framework for coordination in various collective action situations. It has been shown that formally representing and reasoning with (electronic) social capital can reduce the complexity of decision-making, enhance participation and improve outcomes of collective action. However, it was assumed that these institutions were essentially independent, and so the members were limited in their ability to fully exploit their social capital across different collective actions situations because they did no learning. Therefore, in this paper we examine the role and nature of social capital with learning agents in the context of Ostrom's institutional design principle regarding structural self-organisation, specifically in the form of multiple layers of nested enterprises. Both inter-agent and inter-institutional interactions are then situated in a Public Goods Game, typically used to study the effects of free-riding which diminishes the positive benefits of cooperation in otherwise unregulated situations. Our experimental results demonstrate that the Social Capital created both within and between the institutions beneficially affects the development of a bottom-up structure of nested enterprises.

Social capital has been defined as an attribute of individuals that facilitates cooperation to achieve mutual benefit, and enhances a group's capability to solve collective action problems. In this paper, we formalise a new computational framework for optimising self-organised collective action using electronic social capital. This framework comprises event handlers which update multivariate forms of social capital (trustworthiness, social network, and institutions), and a set of metrics over these forms that provide inputs to social decision-making processes. We implement an experimental multi-agent test bed where a number of agents iteratively play simultaneous n-player games, and use the social capital framework for their action-selection. Our results show that social capital optimises outcomes (in terms of long-term satisfaction and utility), reduces the complexity of decision making, and allows the system to scale to support self-organising collective action in 'large' groups.

The traditional mediterranean diet is associated with a hope for longer survival. It has also been shown that the red wine possesses a protective effect against the oxidative stress. We studied TAC, the DHEAS and the IGF-1 in a group of 26 healthy centenarians, 17 women and 9 men, of the age range of 100--105 years. Furthermore, we analyzed also serum urate and bilirubin levels between drinkers and abstainers. Most of centenarian subjects have been moderate wine consumers (500 ml/day of red wine). These subjects were subdivided as follows: (i) Group A: those who had maintained the style of their dietary habits as compared to the previous years (n=3 males, 10 females); (ii) Group B: those who actually consumed a diet being deficient compared to that of the previous years, but remained moderate drinkers of red wine (n=3 males, 4 females); and (iii) Group C: those who actually consumed a diet being deficient compared to that of the previous years, and at the same time, were abstainers in wine consumption (n=3 males, 3 females). The results show that in men three of the studied parameters decreased from Group A to C to considerable extents, as follows (mean+/-S.D.). TAC: 302.4+/-32.3; 142.0+/-24.1 and 96.4+/-20.1 micromol/l; DHEAS: 3.35+/-0.81; 2.52+/-0.18 and 1.34+/-0.14 micromol/l; IGF-1: 85.7+/-6.7; 76.6+/-6.7 and 65.6+/-2.6 ng/ml, respectively. For the same parameters, the results in the women were: TAC: 258.4+/-12.2; 182.1+/-14.0 and 107.6+/-10.0 micromol/l; DHEAS: 3.85+/-0.16; 2.34+/-0.19 and 2.05+/-0.04 micromol/l; IGF-1: 89.7+/-6.7; 76.6+/-4.7 and 64.2+/-2.7 ng/ml, respectively. We did not find any significant difference in the other serum parameters between drinkers (n=14) and abstainers (n=3) (urate: 267.6+/-52.9, and 289.5+/-80.1; bilirubin: 9.81+/-4.29 and 7.18+/-2.89 micromol/l, respectively). Our data suggest that the deteriorated diet caused a reduction of TAC, DHEAS and IGF-1 in the centenarians. However, red vine consumption exerted a protective effect against this trend, even if this protection is not reaching statistical significance in some cases (in men), which is due most probably to the lower number of male subjects in the study.

A common requirement of distributed multi-agent systems is for the agents themselves to negotiate pairwise agreements on performing a joint action. In systems with endogenous resources, the cost of computing the decision-making has to be taken into account. If the computational resources expended in negotiating an optimal solution exceed the marginal benefits gained from that negotiation, then it would be more expedient and efficient to use the memory of past interactions to short-cut the complexity of decision-making in joint or collective actions of this kind. In social systems, it has been observed that social capital is an attribute of individuals that enhances their ability to solve collective action problems. In this paper, we define a new computational framework for representing and reasoning about electronic social capital, in which actions enhance or diminish three different forms of social capital (individual trustworthiness, social network, and institutions), and a decision-making model which uses social capital to decide whether to cooperate or defect in strategic games. A set of scenarios are presented where we believe that social capital can support effective collective action sustained over time, avoid suboptimal dominant strategies, and short-cut the computational costs involved in repetitious solving of strategic games.

In this paper we describe the tool we have developed to visualise experimental data on top of the multi-agent simulation platform Presage2 and how we have used it with our Social Capital Framework. The visualisation demonstrates how social capital can be used to self-organise solutions to collective actions problems.

In applying the methodology of sociologically-inspired computing to the idea of self-governing institutions for common-pool resource management, an algorithmic basis for self-organising resource allocation in open computer systems and networks has been established. This algorithmic base is not intended to be a testable model of how people manage decentralised resource allocation: on the other hand, it does raise the issue of: what happens when these computer models are made manifest in socio-technical systems for management of resources like energy, water, transport, and so on. This chapter investigates this issue from the perspective of decentralised Community Energy Systems, in which societies of people and societies of ‘agents’ are interleaved in a form of collective social intelligence. Two systems for demand-side self-organisation are presented, one based on collective awareness in a ‘serious game’, the other based on representation and reasoning with an electronic form of social capital. These systems suggest an implementation route for socio-technical systems, comprising both people and agents, in which ‘fair’ treatment of people is grounded in algorithms executed by the agents.

In Smart Grids, flexible demand can lower the consumption peaks by flattening the demand curve. Since a centralised approach to allocate electricity consumption suffers from scalability issues, we proposed a self-organising solution in which consumers exchange allocated electricity consumption slots to satisfy their preferences. In addition, cooperation is encouraged using social capital, consumers can help each other in order to obtain the allocations they need.

The clinical features and the laboratory aspects of the amiodarone-induced hypothyroidism (AIH) in the elderly as well as the effects of amiodarone treatment in aged AIH people have not yet been well clarified. In the present paper, we evaluated 18 subjects of both sexes (7 females, 11 males), aged 65-83 years, affected by AIH, recruited in Central Tuscany, Italy. The patients were divided in two subsets on the basis of thyroid stimulating hormone (TSH) values: mild (TSH20 mU/l; Group A, n=11) and severe (TSH20 mU/l; Group B, n=7) hypothyroid patients. On the basis of clinical features, hypothyroidism was diagnosed only in two patients (out of Group B). Concerning the hormonal pattern, we found that free tetraiodothyronine (fT4) levels were significantly lower than the normal range only in Group B subjects; TSH and thyroglobulin were higher than normal in both groups; free triiodothyronine (fT3) were always in the normal range. Thyroid autoantibodies were found positive only in one patient out of Group A and in two patients out of Group B. In 5/18 patients T4 substitutive therapy was rapidly assigned, because of severe degree of hypothyroidism. In the remaining 13/18 patients, we evaluated the clinical behavior of AIH. After additional cardiac evaluation, amiodarone was withdrawn in 5/13 patients: during follow-up period (4-10 months) four patients became quickly euthyroid while one worsened. In 8/13 patients, amiodarone treatment had to be carried on; during follow-up (2-48 months), four patients remained mildly hypothyroid, while other four patients became severely hypothyroid. In conclusion, in amiodarone treated elderly people, diagnosis of hypothyroidism is reliable only on the basis of high values of TSH; clinical features and fT3 serum levels never enable diagnosis.

Free radicals are considered important factors in biological aging (1). Consequently, there is increasing interest in the mechanisms of antioxidant protection against free-radical-induced injury and in identification of suitable biochemical indicators for measuring serum antioxidant capacity (SAC) (2). Several methods have been proposed for the measurement of SAC, including the enhanced chemiluminescence assay used in this study (3). This technique is calibrated with Trolox™, a water-soluble vitamin E analog (Hoffmann–La Roche, obtained from Aldrich Chemical Co., Gillingham, Dorset, UK), and assay results are expressed as μmol/L Trolox equivalents. We measured serum SAC in 58 healthy subjects: 37 adults (19 men and 18 women, age range 18–91 years) and 21 centenarians …