https://research-explorer.ista.ac.at 2000-01-01T00:00+00:00 1 weekly https://research-explorer.ista.ac.at/record/19903 Hübner, Valentin ; https://orcid.org/0009-0001-5009-4987 2025 Cooperation, that is, one person paying a cost for another's benefit, is a fundamental principle without which no form of society could exist. The extent to which humans cooperate with each other is also an essential feature that differentiates them from other animals. Cooperation occurs even in the absence of altruistic motivations, when it is selfishly incentivised by the expectation of a future reward. For example, many economic interactions are well described that way. This kind of cooperation requires that people exhibit reciprocal behaviour that acts as a mechanism that rewards cooperation. With game-theoretic models, it is possible to formally study potential such mechanisms and under what conditions they can exist. This thesis contributes to this effort by analysing recently introduced models of cooperation that advance on previous work by taking into account the potential for pre-existing inequality among cooperating individuals as well as the different forms that reciprocity can take. Individuals may differ both intrinsically, in their abilities, as well as extrinsically, in the amount of resources they have available. Allowing for such differences in a model of cooperation helps to understand how inequality affects the potential for, and outcomes of, cooperation among unequals. In this thesis, it is shown that in the presence of intrinsic inequality, a similar unequal distribution of resources can increase the potential for cooperation. This effect is stronger the smaller the group is in which cooperation takes place. It is also shown that under particular assumptions, if the unequal members of a group vary the size of their contributions to a cooperative effort over time, they can thereby increase their efficiency and improve the collective outcome. Cooperative behaviour in a two-person interaction can be rewarded either by direct reciprocation whenever the same two people interact again, or indirectly by a third party who observed the interaction. In the latter case of indirect reciprocity, individuals are proximally rewarded by a good reputation, which ultimately translates to being rewarded with cooperative behaviour by others. This mechanism can enable selfishly motivated cooperation even in circumstances where individuals are unlikely to meet again, akin to how money facilitates trade. While these two forms of reciprocity have mostly been studied in isolation, this thesis analyses both direct and indirect reciprocity in a general model in order to compare their relative effectiveness under different circumstances. The contribution of this thesis is an extension of previous work regarding a specific kind of interaction, whose parameters allow for convenient mathematical analysis, to the most general set of possible interactions. https://research-explorer.ista.ac.at/record/19903 https://research-explorer.ista.ac.at/download/19903/19976 eng Institute of Science and Technology Austria info:eu-repo/semantics/altIdentifier/doi/10.15479/AT-ISTA-19903 info:eu-repo/semantics/altIdentifier/issn/2663-337X info:eu-repo/semantics/openAccess Hübner V. Reciprocity and inequality in social dilemmas. 2025. doi:<a href="https://doi.org/10.15479/AT-ISTA-19903">10.15479/AT-ISTA-19903</a> ddc:519 Reciprocity and inequality in social dilemmas ISTA Thesis info:eu-repo/semantics/doctoralThesis doc-type:doctoralThesis text http://purl.org/coar/resource_type/c_db06 https://research-explorer.ista.ac.at/record/9402 Schmid, Laura ; https://orcid.org/0000-0002-6978-7329 Chatterjee, Krishnendu ; https://orcid.org/0000-0002-4561-241X Hilbe, Christian ; https://orcid.org/0000-0001-5116-955X Nowak, Martin A. 2021 Direct and indirect reciprocity are key mechanisms for the evolution of cooperation. Direct reciprocity means that individuals use their own experience to decide whether to cooperate with another person. Indirect reciprocity means that they also consider the experiences of others. Although these two mechanisms are intertwined, they are typically studied in isolation. Here, we introduce a mathematical framework that allows us to explore both kinds of reciprocity simultaneously. We show that the well-known ‘generous tit-for-tat’ strategy of direct reciprocity has a natural analogue in indirect reciprocity, which we call ‘generous scoring’. Using an equilibrium analysis, we characterize under which conditions either of the two strategies can maintain cooperation. With simulations, we additionally explore which kind of reciprocity evolves when members of a population engage in social learning to adapt to their environment. Our results draw unexpected connections between direct and indirect reciprocity while highlighting important differences regarding their evolvability. https://research-explorer.ista.ac.at/record/9402 https://research-explorer.ista.ac.at/download/9402/14496 eng Springer Nature info:eu-repo/semantics/altIdentifier/doi/10.1038/s41562-021-01114-8 info:eu-repo/semantics/altIdentifier/e-issn/2397-3374 info:eu-repo/semantics/altIdentifier/wos/000650304000002 info:eu-repo/semantics/altIdentifier/pmid/33986519 info:eu-repo/semantics/openAccess Schmid L, Chatterjee K, Hilbe C, Nowak MA. A unified framework of direct and indirect reciprocity. <i>Nature Human Behaviour</i>. 2021;5(10):1292–1302. doi:<a href="https://doi.org/10.1038/s41562-021-01114-8">10.1038/s41562-021-01114-8</a> ddc:000 A unified framework of direct and indirect reciprocity info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1 https://research-explorer.ista.ac.at/record/20859 Company-Garrido, Iván Zurita Carpio, Alberto Colomer-Rosell, Mariona Ciraulo, Bernard Molkenbur, Ronja Lanzerstorfer, Peter Pezzano, Fabio Agazzi, Costanza Hauschild, Robert ; https://orcid.org/0000-0001-9843-3522 Jain, Saumey Jacques, Jeroen M. Venturini, Valeria Knapp, Christian Xie, Yufei Merrin, Jack ; https://orcid.org/0000-0001-5145-4609 Weghuber, Julian Schaaf, Marcel Quidant, Romain Kiermaier, Eva ; https://orcid.org/0000-0001-6165-5738 Ortega Arroyo, Jaime Ruprecht, Verena ; https://orcid.org/0000-0003-4088-8633 Wieser, Stefan ; https://orcid.org/0000-0002-2670-2217 2025 Effective immune responses rely on the efficient migration of leukocytes. Yet, how temperature regulates migration dynamics at the single-cell level has remained poorly understood. Using zebrafish embryos and mouse tissue explants, we found that temperature positively regulates leukocyte migration speed, exploration, and arrival frequencies to wounds and lymph vessels. Complementary 2D and 3D cultures revealed that this thermokinetic control of cell migration is conserved across immune cell types, independently of the 3D tissue environment. By applying precise (sub-)cellular temperature modulation, we identified a rapid and reversible thermo-response that depends on myosin II activity. Small physiological increases in temperature (1°C –2°C), as present during fever-like conditions, profoundly increased immune responses by accelerating arrival times at lymphatic vessels and tissue wounds. These findings identify myosin-II-dependent actomyosin contractility as a critical mechanical structure regulating single-cell thermo-adaptability, with physiological implications for tuning the speed of immune responses in vivo. https://research-explorer.ista.ac.at/record/20859 eng Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.devcel.2025.10.006 info:eu-repo/semantics/altIdentifier/issn/1534-5807 info:eu-repo/semantics/altIdentifier/e-issn/1878-1551 info:eu-repo/semantics/altIdentifier/pmid/41192429 info:eu-repo/semantics/openAccess Company-Garrido I, Zurita Carpio A, Colomer-Rosell M, et al. Myosin II regulates cellular thermo-adaptability and the efficiency of immune responses. <i>Developmental Cell</i>. 2025. doi:<a href="https://doi.org/10.1016/j.devcel.2025.10.006">10.1016/j.devcel.2025.10.006</a> ddc:570 Myosin II regulates cellular thermo-adaptability and the efficiency of immune responses info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1 https://research-explorer.ista.ac.at/record/20329 Ibáñez, Maria ; https://orcid.org/0000-0001-5013-2843 Boehme, Simon C. Buonsanti, Raffaella De Roo, Jonathan Milliron, Delia J. Ithurria, Sandrine Rogach, Andrey L. Cabot, Andreu Yarema, Maksym Cossairt, Brandi M. Reiss, Peter Talapin, Dmitri V. Protesescu, Loredana Hens, Zeger Infante, Ivan Bodnarchuk, Maryna I. Ye, Xingchen Wang, Yuanyuan Zhang, Hao Lhuillier, Emmanuel Klimov, Victor I. Utzat, Hendrik Rainò, Gabriele Kagan, Cherie R. Cargnello, Matteo Son, Jae Sung Kovalenko, Maksym V. 2025 Nanocrystals (NCs) of various compositions have made important contributions to science and technology, with their impact recognized by the 2023 Nobel Prize in Chemistry for the discovery and synthesis of semiconductor quantum dots (QDs). Over four decades of research into NCs has led to numerous advancements in diverse fields, such as optoelectronics, catalysis, energy, medicine, and recently, quantum information and computing. The last 10 years since the predecessor perspective “Prospect of Nanoscience with Nanocrystals” was published in ACS Nano have seen NC research continuously evolve, yielding critical advances in fundamental understanding and practical applications. Mechanistic insights into NC formation have translated into precision control over NC size, shape, and composition. Emerging synthesis techniques have broadened the landscape of compounds obtainable in colloidal NC form. Sophistication in surface chemistry, jointly bolstered by theoretical models and experimental findings, has facilitated refined control over NC properties and represents a trusted gateway to enhanced NC stability and processability. The assembly of NCs into superlattices, along with two-dimensional (2D) photolithography and three-dimensional (3D) printing, has expanded their utility in creating materials with tailored properties. Applications of NCs are also flourishing, consolidating progress in fields targeted early on, such as optoelectronics and catalysis, and extending into areas ranging from quantum technology to phase-change memories. In this perspective, we review the extensive progress in research on NCs over the past decade and highlight key areas where future research may bring further breakthroughs. https://research-explorer.ista.ac.at/record/20329 https://research-explorer.ista.ac.at/download/20329/20909 eng American Chemical Society info:eu-repo/semantics/altIdentifier/doi/10.1021/acsnano.5c07838 info:eu-repo/semantics/altIdentifier/issn/1936-0851 info:eu-repo/semantics/altIdentifier/e-issn/1936-086X info:eu-repo/semantics/altIdentifier/wos/001562960800001 info:eu-repo/semantics/altIdentifier/pmid/40902118 info:eu-repo/semantics/openAccess Ibáñez M, Boehme SC, Buonsanti R, et al. Prospects of nanoscience with nanocrystals: 2025 edition. <i>ACS Nano</i>. 2025;19(36):31969–32051. doi:<a href="https://doi.org/10.1021/acsnano.5c07838">10.1021/acsnano.5c07838</a> ddc:540 Prospects of nanoscience with nanocrystals: 2025 edition info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_dcae04bc