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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.

The human functional autonomy is reduced progressively with advancing age, although a considerable proportion of the centenarians maintain a good level of autosufficiency for the basic performance of the everyday life. Even if males have a lower probability to reach the centenarian age than females do, the male centenarians display generally better functional conditions than the females. Actually, there are no systemic studies on centenarian works or activities; nevertheless, the examples of several representative persons (artists, scientists, explorers, etc.) who remained active even after this age indicate that such a possibility is realistic, and that the maintenance of vital interest and passions, thus preserving competence and professional attitudes, is not in conflict with the reaching of extreme longevity.

Centenarians represent a group of population displaying the most rapid expansion. This progressive increase of the presence of centenarians is a multi-factorial phenomenon, which is due to the improvements of the environmental conditions and the life style and also to the progress of the medical science. In order to obtain a more reliable estimate of the longevity per gender and territorial entities, we propose two new indicators. (i) The ratio between the ultranonagenarians and the total population above 65 years old (called longevity index: LI%); (ii) the ratio between the centenarians and the total population above 90 years old (called centenarity index: CI%). An analysis of the data of the Italian National Office of Statistics (ISTAT, www.istat.it/Popolazione/Demo) using these two indicators demonstrates that the subjects above the age of 90 are more frequent in the regions of Central and Northern Italy, which are more developed regarding the economic conditions and technological progress. Nevertheless, the Southern and Insular regions of Italy have a higher occurrence of centenarians among the ultranonagenarian population, and also a higher prevalence of male centenarians, as compared to the northern regions. This demonstrates that achievement of the threshold of 100 years old does not require only particular socio-economic conditions, but also an adequate climate and environment, as well as a favorable genetic composition.

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 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.

Social scientist define social capital as a feature or attribute of an organisation or an individual that facilitates cooperation to achieve mutual benefit and enhances their ability to solve collective action problems. In this paper we present a set of experiments on an electronic version of social capital in two different scenarios of repeated pairwise interactions amongst agents. The results show that (i) social capital can be represented in a computational form, and (ii) that the use of social capital does indeed support effective collective action. These results offer a convincing demonstration that being able to represent and reason about (electronic) social capital provides a compelling alternative solution to cooperation dilemmas in multi-agent systems.

The biochemistry of reactive oxygen species is an important field with wide implications. Both preventive and chain breaking antioxidants have a role in the limitation of oxidative stress that accompanies aging and diseases. The potent antioxidant activity of phenolic substances of red wine, in particular, have been proposed as an explanation for the "French Paradox" (the apparent incompatibility of a high fat diet with a low incidence of coronary heart diseases). A lot of researchers emphasize beneficial effects of red wine and insist on lower or no antioxidant effect of white wine. We have been studying the effect of both white and red wine on blood antioxidant capacity in humans. The white wine we have been testing was produced by an ancient Tuscany procedure (the same used for red winemaking) which includes fermentation with grapes juice together with peelings and seeds. A statistically significant increase in total antioxidant capacity (TAC) levels was observed after 2h from red or white wine ingestion. White wine effect appears to be faster than that of the red one, since a significant difference can also be reported after 1h. We can conclude that the big difference in the results of serum TAC due to white wine reported by us, in comparison to those reported by others relatively to white wine produced using the French method, can be explained by the difference in the winemaking procedure we adopted.

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.

Usually, the effects of cognitive decline are not noted before the age of 70 years, which involve the intellectual capacities, the attention, the processes of elaboration and the memory. The studies on the cognitive disturbances of the elderly are numerous, and document the progressive increase of cerebral deterioration with advancing age. However, only a few studies refer to the significance of the cognitive disturbances in the clinical conditions and autonomy of the long living subjects. For this reason, we studied the cerebral deterioration of an adequate number of centenarians in correlation with their clinical conditions and autonomy. Our centenarian sample derived from the Italian multi-center study on centenarians (IMUSCE), which was an epidemiological study which identified 1173 centenarians (202 males, 971 females) in the age range of 100–109 years. From this sample, we analyzed 346 subjects as far as the cognitive functions and the degree of autonomy by using the psychometric tests of the mini-mental state examination (MMSE) and the instrumental activities of daily living (IADL) for the functional evaluations. In addition, we evaluated the clinical conditions of the subjects dividing them in three groups: Group A (those in good clinical conditions), Group B (those in discrete clinical conditions), and Group C (those in deteriorated clinical conditions). These analyses revealed that 187 (54.1%) of the 346 examined centenarians have shown an MMSE score in the normal range (score ratio from 1.0 to 0.63). The cognitive disorders are present in the centenarians in a clearly higher frequency (13.1%), than found in the common elderly (5.1%). The severe cognitive disorders do not allow a total autonomy or even a slight dependency. Only six subjects (1.7%) of the total sample were totally independent. These subjects had no cognitive disorders, and were in good clinical conditions. The results show that having an MMSE score in the normal range, and being in good clinical conditions are necessary but not sufficient prerequisites for a total autonomy in the IADL scores.

Statistical data of Italy, issued on 1st January 2005, show that Tuscany has a high percentage of elderly subjects, and that to reach 100 years is a common possibility, mainly for women. Comparable values appear for longevity index (LI%), either calculated on the basis of the various resorts above sea level, or on the basis of the number of inhabitants. However, some differences are observed considering the various provinces: Grosseto Province has the second higher value of >65-year-old subjects, while its LI% is the lowest. Centenarity index (CI%) considerably differs from LI%: if ranking Tuscany according to the various heights of territorial positions, the first displays a negative, while the second one shows a positive correlation with the local height. If comparing for inhabitants number, CI% is maximal in provincial cities, while LI% is higher in smaller communities. All these data indicate that residents in small communities of the mountains reach easily 90 years, while 100 years are more frequently reached in larger cities in the plane areas. In conclusion, the highest province longevity (Lucca) coincides with the highest centenarian sex ratio, and it suggests that in this province the older women may enjoy particular forms of environmental protection, which helps them for reaching 100 years of age. Differences between the results of this study and others performed in Sardinia are discussed.

Background In eastern North America two common colour morphs exist in most populations of redback salamanders (Plethodon cinereus). Previous studies have indicated that the different morphs may be adapted to different thermal niches and the morphological variation has been linked to standard metabolic rate at 15°C in one population of P. cinereus. It has therefore been hypothesized that a correlated response to selection on metabolic rate across thermal niches maintains the colour polymorphism in P. cinereus. This study tests that hypothesis. Results We found that the two colour morphs do sometimes differ in their maintenance metabolic rate (MMR) profiles, but that the pattern is not consistent across populations or seasons. We also found that when MMR profiles differ between morphs those differences do not indicate that distinct niches exist. Field censuses showed that the two colour morphs are sometimes found at different substrate temperatures and that this difference is also dependent on census location and season. Conclusion While these morphs sometimes differ in their maintenance energy expenditures, the differences in MMR profile in this study are not consistent with maintenance of the polymorphism via a simple correlated response to selection across multiple niches. When present, differences in MMR profile do not indicate the existence of multiple thermal niches that consistently mirror colour polymorphism. We suggest that while a relationship between colour morph and thermal niche selection appears to exist it is neither simple nor consistent.

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 to be important factors involved in many physiopathological processes. Several methods have been proposed for studying the mechanisms of antioxidant protection against free radical-induced injury, including the measurement of the total antioxidant capacity (TAC) in body fluids, based on enhanced chemiluminescence. This technique is calibrated against Trolox and assay results are expressed as mumol/L of Trolox equivalents. Since many of the complications induced by diabetes appear to be mediated by oxygen free radical generation, we have investigated serum antioxidant capacity in a group of healthy subjects and in insulin-dependent diabetic (IDDM) subjects. A statistically significant difference was noticed in TAC values between the IDDM group and the young control group. Even if the biological meaning of this significant reduction in TAC remains to be explained, an overproduction of precursors of reactive oxygen free radicals and/or a decreased scavenger systems efficiency can be associated with the increased risk of atherosclerotic cardiovascular disease in diabetic patients.

Na + /K + - and Ca 2 +-ATPase are the major ATP-dependent membrane-bound enzymes that regulate the cation transmembrane gradient which is altered both in red blood cell (RBC) senescence and in RBCs of diabetic patients. In an attempt to clarify the possible connection between diabetes mellitus and ageing, we investigated the relationship between RBC ATP content, Na + /K + -ATPase, Ca 2+ -ATPase activities and ageing in healthy, insulin-dependent (IDDM) and non-insulin-dependent (NIDDM) subjects. A significant correlation was found (r = -082; P < 0.001) between RBC ATP content and subject's age only in the control group. A significant reduction in Na + /K + -ATPase activity was observed in the older group (C 2 ) of control subjects, in comparison with the younger (C 1 ) one. In both IDDM and NIDDM subjects, the enzymatic activity was significantly decreased when compared with healthy subjects of similar age (P < 0.001). A significant negative correlation was found between age and enzymatic activity in healthy subjects (r= -0.60; P

We investigated the significance of adenosine triphosphate (ATP) release from diabetic subjects' red blood cells (RBCs) following osmotic shock (OS) and its possible relationship with hemoglobin A1C (HbA1C) and with the RBC membrane protein skeleton. RBCs from type I (insulin-dependent [IDDM]) and type II (non-insulin-dependent [NIDDM]) diabetic subjects and age- and sex-matched control subjects were submitted to OS using NaCl solutions (from 0.9% to 0.045% final concentration). ATP release values were determined by the bioluminescent method. For pattern study, they were expressed both as absolute values and as percentages (%) of ATP maximum release (at 0.045% NaCl solution). Twenty-seven IDDM and 25 NIDDM subjects and two control groups were investigated. ATP content in RBCs was 2.08 +/- 0.19 pmol/10(4) RBC in IDDM and 1.23 +/- 0.20 pmol/10(4) RBC in NIDDM subjects. The ATP content of IDDM subjects' RBCs was significantly higher than that of the corresponding control group. ATP release at 0.49% NaCI OS, both as absolute value and as percentage value, was significantly lower in both diabetic groups, and ATP% was inversely correlated with HbA1" (IDDM: r = -.489, P.01; NIDDM: r = -.654, P.01), suggesting a possible relationship between Hb glycation, RBC membrane protein skeleton glycation, and its influence on ATP release by OS. In conclusion, the proposed method seems useful for measuring RBC ATP content and, at the same time, for monitoring the leak effect of the RBC membrane before it bursts.

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 …

The fatty acid composition of adipose tissue from normal, atherosclerotic and diabetic men and women was studied. We found a difference in the fatty acid composition between both sexes. A decrease in linoleic acid and an increase in palmitic and stearic acids in adipose tissue from atherosclerotic men was shown, while there was an increase in palmitic acid in adipose tissue from atherosclerotic women. An increase in oleic acid was found in diabetic men. This alteration in the fatty acid content of adipose tissue may be related to some modification in the metabolism of this tissue due either to atherosclerosis or to diabetes which cause an alteration of the lipid metabolism.

The authors have investigated the effect of pentoxifylline administration (400 mg in three doses) in diabetic subjects with lower limb vasculopathy. The results have shown a marked improvement in clinical symptoms and VRBC and a slight improvement in fibrinogen and blood lipid levels.