΄΄Η Ελλάδα και οι οικονομικές κρίσεις΄΄ Από την κρίση του 1929 στην κρίση του σήμερα: Οικονομικές & Κοινωνικές Διαστάσεις

Η ανά χείρας εργασία αυτό το οποίο πραγματεύεται είναι τις δύο, απ’ τις τρεις, μεγάλες οικονομικές κρίσεις που έως τώρα έχει γνωρίσει ο κόσμος, αυτή του 1929 και την αντίστοιχη του 2008, και πως αυτές επηρέασαν την Ελλάδα στους τομείς της οικονομίας και της κοινωνίας. Το πρώτο μέρος της εργασίας αφορά την κρίση του 1929 και εξετάζει τα δεδομένα της εποχής, τόσο πριν όσο κατά τη διάρκεια και έπειτα αυτής, δίνοντας έτσι μία ολοκληρωμένη εικόνα για την Ελλάδα του Μεσοπολέμου και τις συνθήκες που επικρατούσαν, ενώ παράλληλα εξετάζονται και ορισμένες αντιφάσεις που υπάρχουν σ’ αυτή, όπως το γεγονός πως η οικονομία του κράτους παρουσίαζε σημάδια εκσυγχρονισμού και ανάκαμψης ενώ παράλληλα το δημόσιο χρέος είχε εκτοξευθεί, πράγμα που οδήγησε και στην πτώχευση του 1932. Στο δεύτερο μέρος και αφού προηγουμένως έχει εξετασθεί η περίοδος του Κραχ, αρχίζει να αναπτύσσεται και να εξετάζεται η διεθνοποίηση της οικονομίας, τα χρόνια της μεταπολίτευσης και πως άλλαξε τόσο η οικονομία και η κοινωνία από τότε έως και το 2008. Αφού καλυφθούν τα παραπάνω, η εργασία επικεντρώνεται στη δεκαετία που έχει μεσολαβήσει μεταξύ της κρίσης και του σήμερα, εξετάζοντας και παραθέτοντας στοιχεία για τις επιπτώσεις αυτής σε ένα ευρύ κοινωνικό και οικονομικό φάσμα. Τέλος αφού έχουν εξεταστεί και οι δύο περίοδοι ξεχωριστά επιχειρείται μία σωρευτική προσέγγιση των δύο και των επιπτώσεων που επέφερε, επιφέρει ή εν δυνάμει μπορεί να επιφέρει η κάθε μία.This paper deals with two of the three major economic crises that the world has seen so far, the 1929 and the 2008, and how they affected Greece in the fields of economy and society. The first part of the work concerns the 1929 crisis and examines the data of the time, both before and after it, thus giving a comprehensive picture of interwar Greece and the conditions that prevailed, while also examining some contradictions such as the fact that the economy of the state was showing signs of modernization and recovery, while the public debt was launched, which led to the bankruptcy of 1932. In the second part and after examining the Krah period, the internationalization of the economy, the years of the post-conflict, and how the economy and society have changed since then until 2008 are beginning to develop and be explored. Having covered the above, the work focuses on the decade between the crisis and today, looking at and reporting on its impact on a broad social and economic spectrum. Finally, after both periods have been examined, a cumulative approach of the two is attempted, and the impact that each of them has, either potentially,can bring about

Dynamics of growth factor production in monolayers of cancer cells and evolution of resistance to anticancer therapies

Tumor heterogeneity is well documented for many characters, including the production of growth factors, which improve tumor proliferation and promote resistance against apoptosis and against immune reaction. What maintains heterogeneity remains an open question that has implications for diagnosis and treatment. While it has been suggested that therapies targeting growth factors are robust against evolved resistance, current therapies against growth factors, like antiangiogenic drugs, are not effective in the long term, as resistant mutants can evolve and lead to relapse. We use evolutionary game theory to study the dynamics of the production of growth factors by monolayers of cancer cells and to understand the effect of therapies that target growth factors. The dynamics depend on the production cost of the growth factor, on its diffusion range and on the type of benefit it confers to the cells. Stable heterogeneity is a typical outcome of the dynamics, while a pure equilibrium of nonproducer cells is possible under certain conditions. Such pure equilibrium can be the goal of new anticancer therapies. We show that current therapies, instead, can be effective only if growth factors are almost completely eliminated and if the reduction is almost immediate

The animal nature of spontaneous human laughter

a b s t r a c t a r t i c l e i n f o Laughter is a universally produced vocal signal that plays an important role in human social interaction. Researchers have distinguished between spontaneous and volitional laughter, but no empirical work has explored possible acoustic and perceptual differences. If spontaneous laughter is an honest signal of cooperative intent (e.g., derived from play breathing patterns), then the ability to mimic these sounds volitionally could have shaped perceptual systems to be attuned to aspects of spontaneous laughs that are harder to fake-features associated with phylogenetically older vocal control mechanisms. We extracted spontaneous laughs from conversations between friends and volitional laughs elicited by instruction without other provocation. In three perception experiments we found that, 1) participants could distinguish between spontaneous and volitional laughter, 2) when laugh speed was increased (duration decreased 33% and pitch held constant), all laughs were judged as more "real," with judgment accuracy increasing for spontaneous laughter and decreasing for volitional laughter, and 3) when the laughs were slowed down (duration increased 260% and pitch altered proportionally), participants could not distinguish spontaneous laughs from nonhuman vocalizations but could identify volitional laughs as human-made. These findings and acoustic data suggest that spontaneous and volitional laughs are produced by different vocal systems, and that spontaneous laughter might share features with nonhuman animal vocalizations that volitional laughter does not

Random mobility and spatial structure often enhance cooperation

The effects of an unconditional move rule in the spatial Prisoner's Dilemma, Snowdrift and Stag Hunt games are studied. Spatial structure by itself is known to modify the outcome of many games when compared with a randomly mixed population, sometimes promoting, sometimes inhibiting cooperation. Here we show that random dilution and mobility may suppress the inhibiting factors of the spatial structure in the Snowdrift game, while enhancing the already larger cooperation found in the Prisoner's dilemma and Stag Hunt games.Comment: Submitted to J. Theor. Bio

Monotonicity of Fitness Landscapes and Mutation Rate Control

A common view in evolutionary biology is that mutation rates are minimised. However, studies in combinatorial optimisation and search have shown a clear advantage of using variable mutation rates as a control parameter to optimise the performance of evolutionary algorithms. Much biological theory in this area is based on Ronald Fisher's work, who used Euclidean geometry to study the relation between mutation size and expected fitness of the offspring in infinite phenotypic spaces. Here we reconsider this theory based on the alternative geometry of discrete and finite spaces of DNA sequences. First, we consider the geometric case of fitness being isomorphic to distance from an optimum, and show how problems of optimal mutation rate control can be solved exactly or approximately depending on additional constraints of the problem. Then we consider the general case of fitness communicating only partial information about the distance. We define weak monotonicity of fitness landscapes and prove that this property holds in all landscapes that are continuous and open at the optimum. This theoretical result motivates our hypothesis that optimal mutation rate functions in such landscapes will increase when fitness decreases in some neighbourhood of an optimum, resembling the control functions derived in the geometric case. We test this hypothesis experimentally by analysing approximately optimal mutation rate control functions in 115 complete landscapes of binding scores between DNA sequences and transcription factors. Our findings support the hypothesis and find that the increase of mutation rate is more rapid in landscapes that are less monotonic (more rugged). We discuss the relevance of these findings to living organisms

The future of evolutionary medicine: sparking innovation in biomedicine and public health

Evolutionary medicine - i.e. the application of insights from evolution and ecology to biomedicine - has tremendous untapped potential to spark transformational innovation in biomedical research, clinical care and public health. Fundamentally, a systematic mapping across the full diversity of life is required to identify animal model systems for disease vulnerability, resistance, and counter-resistance that could lead to novel clinical treatments. Evolutionary dynamics should guide novel therapeutic approaches that target the development of treatment resistance in cancers (e.g., via adaptive or extinction therapy) and antimicrobial resistance (e.g., via innovations in chemistry, antimicrobial usage, and phage therapy). With respect to public health, the insight that many modern human pathologies (e.g., obesity) result from mismatches between the ecologies in which we evolved and our modern environments has important implications for disease prevention. Life-history evolution can also shed important light on patterns of disease burden, for example in reproductive health. Experience during the COVID-19 (SARS-CoV-2) pandemic has underlined the critical role of evolutionary dynamics (e.g., with respect to virulence and transmissibility) in predicting and managing this and future pandemics, and in using evolutionary principles to understand and address aspects of human behavior that impede biomedical innovation and public health (e.g., unhealthy behaviors and vaccine hesitancy). In conclusion, greater interdisciplinary collaboration is vital to systematically leverage the insight-generating power of evolutionary medicine to better understand, prevent, and treat existing and emerging threats to human, animal, and planetary health

Descriptive Norms Caused Increases in Mask Wearing During the COVID-19 Pandemic

Human sociality is governed by two types of social norms: injunctive norms, which prescribe what people ought to do, and descriptive norms, which reflect what people actually do. The process by which these norms emerge and their causal influences on cooperative behavior over time are not well understood. Here, we study these questions through social norms influencing mask wearing during the COVID-19 pandemic. Leveraging 2 years of data from the United States (18 time points; n = 915), we tracked mask wearing and perceived injunctive and descriptive mask wearing norms as the pandemic unfolded. Longitudinal trends suggested that norms and behavior were tightly coupled, changing quickly in response to public health recommendations. In addition, longitudinal modeling revealed that descriptive norms caused future increases in mask wearing across multiple waves of data collection. These cross-lagged causal effects of descriptive norms were large, even after controlling for non-social beliefs and demographic variables. Injunctive norms, by contrast, had less frequent and generally weaker causal effects on future mask wearing. During uncertain times, cooperative behavior is more strongly driven by what others are actually doing, rather than what others think ought to be done

Evolution of Cooperation among Mobile Agents

We study the effects of mobility on the evolution of cooperation among mobile players, which imitate collective motion of biological flocks and interact with neighbors within a prescribed radius $R$. Adopting the prisoner's dilemma game and the snowdrift game as metaphors, we find that cooperation can be maintained and even enhanced for low velocities and small payoff parameters, when compared with the case that all agents do not move. But such enhancement of cooperation is largely determined by the value of $R$, and for modest values of $R$, there is an optimal value of velocity to induce the maximum cooperation level. Besides, we find that intermediate values of $R$ or initial population densities are most favorable for cooperation, when the velocity is fixed. Depending on the payoff parameters, the system can reach an absorbing state of cooperation when the snowdrift game is played. Our findings may help understanding the relations between individual mobility and cooperative behavior in social systems.Comment: 15 pages, 5 figure

Understanding cooperation through fitness interdependence

Some acts of human cooperation are not easily explained by traditional models of kinship or reciprocity. Fitness interdependence may provide a unifying conceptual framework, in which cooperation arises from the mutual dependence for survival or reproduction, as occurs among mates, risk-pooling partnerships and brothers-in-arms

Leave and let leave: A sufficient condition to explain the evolutionary emergence of cooperation

The option to leave your current partner in response to his behavior, also known as conditional dissociation, is a mechanism that has been shown to promote the emergence and stability of cooperation in many social interactions. This mechanism, nevertheless, has always been studied in combination with other factors that are known to support cooperation by themselves. In this paper, we isolate the effect of conditional dissociation on the evolution of cooperation and show that this mechanism is enough to sustain a significant level of cooperation if the expected lifetime of individuals is sufficiently longACCESS (EU, 12-120610), SIMULPAST (MICINN, CSD2010-00034) and SPPORT (JCyL, VA056A12-2). L.R.I. Spanish Ministry of Education for grant JC2009-0026