Einstein, Relativity and Myths

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Was Einstein Really Religious?

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Evolutionary stability and resistance to cheating in an indirect reciprocity model based on reputation

Indirect reciprocity is one of the main mechanisms to explain the emergence and sustainment of altruism in societies. The standard approach to indirect reciprocity is reputation models. These are games in which players base their decisions on their opponent's reputation gained in past interactions with other players (moral assessment). The combination of actions and moral assessment leads to a large diversity of strategies; thus determining the stability of any of them against invasions by all the others is a difficult task. We use a variant of a previously introduced reputation-based model that let us systematically analyze all these invasions and determine which ones are successful. Accordingly, we are able to identify the third-order strategies (those which, apart from the action, judge considering both the reputation of the donor and that of the recipient) that are evolutionarily stable. Our results reveal that if a strategy resists the invasion of any other one sharing its same moral assessment, it can resist the invasion of any other strategy. However, if actions are not always witnessed, cheaters (i.e., individuals with a probability of defecting regardless of the opponent's reputation) have a chance to defeat the stable strategies for some choices of the probabilities of cheating and of being witnessed. Remarkably, by analyzing this issue with adaptive dynamics we find that whether an honest population resists the invasion of cheaters is determined by a Hamilton-like rule, with the probability that the cheat is discovered playing the role of the relatedness parameter.This work has been supported by the Ministerio de Ciencia e Innovación (Spain) through grants MOSAICO and PRODIEVO, by the European Research Area Complexity-Net through grant RESINEE, and by Comunidad de Madrid (Spain) through grant MODELICO-CM. L.A.M.-V. was supported by a postdoctoral fellowship from Alianza 4 Universidades

Povezanost slike o vlastitu tijelu s tjelesnom aktivnošću, zadovoljstvom životom i mediteranskom prehranom španjolskih adolescenata

The aim of this study was to examine the association between physical self-concept and physical activity, the intention to be physically active, life satisfaction, and adherence to the Mediterranean diet in adolescents. A total of 1,808 Spanish adolescents (12-16 years of age) participated in this cross-sectional study. Physical Self Questionnaire, Moderate-to-Vigorous Physical Activity Screening Measure, Intention to be Physically Active Scale, Satisfaction with Life Scale, and Mediterranean Diet Quality Index were administered. The boys with a lower physical self-concept showed higher odd ratios of being inactive, having low intentions of being physically active, poor life satisfaction and low adherence to the Mediterranean diet. Similarly, most of the associations were also statistically significant in girls as well. In conclusion, the study reveals that having a low level of physical self-concept increases the risk of being inactive and of having a low level of intention to be physically active, life satisfaction and adherence to the Mediterranean diet in adolescents.Cilj je ovog istraživanja bio utvrditi povezanost između samopoimanja tijela i tjelesne aktivnosti, namjere da se bude tjelesno aktivan, zadovoljstva životom i pridržavanja mediteranske prehrane kod adolescenata. U ovo transverzalno istraživanje bilo je uključeno ukupno 1.808 španjolskih adolescenata (u dobi od 12 do 16 godina). U istraživanju su korišteni sljedeći mjerni instrumenti: Physical Self Questionnaire, Moderate-to-Vigorous Physical Activity Screening Measure, Intention to be Physically Active Scale, Satisfaction with Life Scale, i Mediterranean Diet Quality Index. Dječaci s nižom razinom zadovoljstva vlastitim tijelom, u bilo kojoj njegovoj dimenziji, pokazali su veću sklonost tjelesnoj neaktivnosti, nižu odlučnost da budu tjelesno aktivni, manifestirali su nisku razinu zadovoljstva životom i slabo pridržavanje načela mediteranske prehrane. Slično kao i kod dječaka, većina relacija bila je statistički značajna i kod djevojčica. Zaključno, istraživanje je ukazalo na činjenicu da niska razina samopoimanja povećava rizik za neaktivnost i za nisku razinu namjere za kasniju tjelesnu aktivnost te da je povezano sa slabijim zadovoljstvom životom i slabijim pridržavanjem načela mediteranske prehrane kod adolescenata

Caustics, catastrophes, and symmetries in curved beams

In this paper, a meaningful classification of optical caustic beams in two dimensions is presented. It is demonstrated that the phase symmetry of the beam's angular spectrum governs the optical catastrophe, which describes the wave properties of ray singularities, for cusp (symmetric phase) and fold (antisymmetric phase) caustics. In contrast to the established idea, the caustic classification arises from the phase symmetry rather than from the phase power, thus breaking the commonly accepted concept that fold and cusp caustics are related to the Airy and Pearcey functions, respectively. Nevertheless, the role played by the spectral phase power is to control the degree of caustic curvature. These findings provide straightforward engineering of caustic beams by addressing the spectral phase into a spatial light modulator or glass plate.Fil: Vaveliuk, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Investigaciones Opticas. Provincia de Buenos Aires. Gobernación. Comision de Invest.científicas. Centro de Investigaciones Opticas. Universidad Nacional de la Plata. Centro de Investigaciones Opticas; ArgentinaFil: Lencina, Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Investigaciones Opticas. Provincia de Buenos Aires. Gobernación. Comision de Invest.científicas. Centro de Investigaciones Opticas. Universidad Nacional de la Plata. Centro de Investigaciones Opticas; ArgentinaFil: Rodrigo, Jose A.. Universidad Complutense de Madrid; EspañaFil: Martinez Matos, Oscar. Universidad Complutense de Madrid; Españ

IHS Discussion: They Were There: Martin Luther King's Visit to UT Austin in 1962

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Position guidelines and evidence base concerning determinants of childhood obesity with a European perspective

Childhood obesity is one of the most pressing global public health issues, with rates increasing fastest in countries at low levels of income. Obesity occurring during childhood is likely to persist throughout the life course, and it is a cause of increased disease risk from the early years of life. This supplement is the result of collaborations involving a large and multidisciplinary group of researchers that were established in the context of the ongoing European Horizon 2020 project Science and Technology in childhood Obesity Policy (STOP). The aim, as in the entire STOP project, is to generate evidence that can support better policies to tackle the problem of childhood obesity in Europe and elsewhere. Quality of life and health well-being concerning children needs to consider personalized, population, and planetary facets to tackle childhood obesity at early stages of life, for in-deep phenotyping, integrating personalized medicine and precision public health interventions at global levels. This supplement contributes to this aim. © 2021 The Authors. Obesity Reviews published by John Wiley & Sons Ltd on behalf of World Obesity Federation

New project innovativeness: The case of Portuguese financial services

Services marketing literature has a tendency to perceive new services as generic and easily imitable. This paper examines the relationship of new services performance determinants (strategic/environment) from the application of a generic model. In particular, we investigate the degree of discontinuity of new projects(innovativeness to market/firm) impacts upon different levels of performance (financial/no-financial). The results of binary logistic regression analysis suggest that the factors that discern best-high marginal success is slightly different, and even lessened, than those that discern successful from unsuccessful innovations. Univariate analysis of variance indicates that there is a significant individual/interactions effect from new product innovativeness (to market/firm)

Dynamic inductive power transfer lane design for e-bikes

This paper presents the concept and initial test results of an inductive lane design capable of dynamic and wirelessly transfer power to electric bicycles (e-bikes). On the lane side, a sequence of oblong primary coils embedded underneath ground surface, along the vehicle path, can be independently excited by high frequency alternating current. The oscillating magnetic field of each primary coil is individually enabled when a Radio Frequency Identification (RFID) tag on board of the e-bike is detected and authenticated by an auxiliary coil laying close to that primary coil. On the e-bike, energy for the powertrain is harvested from the lane by a secondary coil that is installed around its rear wheel. When the e-bike is moving over inter-coil gaps, or anywhere away from the inductive lane, on-board power is sustained with the excess energy stored during transits over energized coils. Preliminary results from a prototyped module demonstrate the feasibility of the system, which could also be used by similarly adapted lightweight electric vehicles, such as rickshaws, electric wheel chairs and other electric personal mobility devices, favoring a new, low cost, sustainable urban modal variant.Research partially supported by grant SFRH/BD/52349/2013 from FCT, the Portuguese funding agency supporting science, technology and innovation, under the scope of the MIT-Portugal Program. L. A. Lisboa Cardoso and J. L. Afonso are with the Centro ALGORITMI, Department of Industrial Electronics, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal (tel. 351-253-510183; e-mails: [email protected], [email protected]). M. Comesaña Martinez and A. A. Nogueiras Meléndez, are with the Department of Electronics Technology, University of Vigo, Vigo, Pontevedra 36310, Spain (e-mail: [email protected])