2,858 research outputs found
Pathways to social evolution: reciprocity, relatedness, and synergy
Many organisms live in populations structured by space and by class, exhibit
plastic responses to their social partners, and are subject to non-additive
ecological and fitness effects. Social evolution theory has long recognized
that all of these factors can lead to different selection pressures but has
only recently attempted to synthesize how these factors interact. Using models
for both discrete and continuous phenotypes, we show that analyzing these
factors in a consistent framework reveals that they interact with one another
in ways previously overlooked. Specifically, behavioral responses
(reciprocity), genetic relatedness, and synergy interact in non-trivial ways
that cannot be easily captured by simple summary indices of assortment. We
demonstrate the importance of these interactions by showing how they have been
neglected in previous synthetic models of social behavior both within and
between species. These interactions also affect the level of behavioral
responses that can evolve in the long run; proximate biological mechanisms are
evolutionarily stable when they generate enough responsiveness relative to the
level of responsiveness that exactly balances the ecological costs and
benefits. Given the richness of social behavior across taxa, these interactions
should be a boon for empirical research as they are likely crucial for
describing the complex relationship linking ecology, demography, and social
behavior.Comment: 4 figure
Vulnerability to purely contagious balance of payment crises in emerging economies: An application to the cases of Russia, Turkey, and Brazil
We explore the possible role of interdependence of expectations in emerging market economies and analyze the crisis transmission mechanism within the ”pure”contagion framework. We consider the cases of Russia, Turkey, and Brazil, and assess whether the fundamentals of these countries allowed for the possibility of ”pure”contagion e¤ects from each other. In particular, we look at Russia - Turkey and Brazil - Russia pairs in year 1997 to see whether Brazilian and the Turkish economies exhibited vulnarability to pure contagion before the 1998 Russian crisis We also repeat the same exercise with the most recent 1999 data. The rationale for choosing these pairings is the huge volume of (luggage) trade between geographical neighbors Russia and Turkey, and the similar export structures of Russia and Brazil (predominantly raw materials) which are continents apart. Our results clearly indicate vulnerability of Brazilian and Turkish economies to high probability of crisis in Russia even in the face of improving fundamentals. In isolation, Brazilian and Turkish fundamentals were not weak enough to place them in a sure-crisis situation. With the incorporation of the Russian link, the multiple equilibria setting disappeared for both countries, rendering sure-crisis as the single equilibrium solution.contagion; balance of payment crisis; emerging economies; Turkey
What are the factors that contribute to aggression in patients with co-occurring antisocial personality disorder and substance abuse?
Background: A significant number of individuals with high levels of aggression have substance use disorder problems. Objective: This study aimed to evaluate the effect of substance use disorder on aggression in young men with Antisocial personality disorder (ASPD). Methods: This cross-sectional study included 328 patients and were diagnosed with ASPD with a comorbidity of substance use disorder, along with 111 healthy young male subjects. Results: The total aggression scores of the patients with a diagnosis of ASPD were significantly higher than those of the healthy group (p < 0.001). Mean scores of aggression subscale, except for indirect aggression, were higher in patients diagnosed with ASPD (p < 0.05). There was a positive correlation between aggression scores and total API scores in patients diagnosed with ASPD (p < 0.001). Aggression scores were higher when subjects were using volatile substances compared to other substances (p < 0.05). Aggression scores increased with duration of substance use disorder (p < 0.001). Discussion: Substance use disorder should be treated first to mitigate aggression in individuals with ASPD. Patients with severe addiction to volatile substances should be given treatment priority. Further studies are necessary to determine the cause of aggression in individuals who abuse substances
Distributed multilevel optimization for complex structures
Optimization problems concerning complex structures with many design variables may entail an unacceptable computational cost. This problem can be reduced considerably with a multilevel approach: A structure consisting of several components is optimized as a whole (global) as well as on the component level. In this paper, an optimization method is discussed with applications in the assessment of the impact of new design considerations in the development of a structure. A strategy based on fully stressed design is applied for optimization problems in linear statics. A global model is used to calculate the interactions (e.g., loads) for each of the components. These components are then optimized using the prescribed interactions, followed by a new global calculation to update the interactions. Mixed discrete and continuous design variables as well as different design configurations are possible. An application of this strategy is presented in the form of the full optimization of a vertical tail plane center box of a generic large passenger aircraft. In linear dynamics, the parametrization of the component interactions is problematic due to the frequency dependence. Hence, a modified method is presented in which the speed of component mode synthesis is used to avoid this parametrization. This method is applied to a simple test case that originates from noise control. \u
Adsorption of platinum oxide (PtO) and platinum dioxide (PtO2) clusters on monolayer aluminium nitride
Bu tezde; ilk olarak tek Pt, O atomları ve PtO, PtO2 ve Pt2O kümelerinin tek tabakalı hekzagonal AlN (h-AlN) üzerine tutunma özelliklerini inceledik. Manyetik olmayan (NM) ve ferromanyetik (FM) durumları göz önünde bulundurularak elektronik ve yük geçişlerini incelemek için yoğunluk fonksiyoneli teorisi kullandık. PtO ve Pt2O tutunmuş AlN sistemi 2 μB manyetik momente sahip FM taban durumunda iken PtO2, Pt ve O tutunması NM yapılara yol açar. Pt tutunmuş AlN sistemi -3. 175 eV ile en düşük tutunma enerjisine sahiptir, bu durum enerjitik olarak en kararlı durumu göstermektedir. Bu özellikler spintronik ve nano elektronikte önemli uygulamalara yol açabilir.In this thesis, we first investigate the adsorption properties of single Pt and O atoms and PtO, PtO2, and Pt2O clusters on hexagonal AlN monolayer. We employ density functional theory (DFT) to study electronic structure and charge transfer of h-AlN by considering nonmagnetic (NM) and ferromagnetic (FM) states. PtO and Pt2O adsorbed h-AlN system has FM ground state with 2.00 mB magnetic moment, while PtO2, Pt, and O adsorption lead to NM structures. Pt adsorbed AlN system has the lowest adsorption energy with -3.175 eV indicating the most stable structure energetically. These properties can lead to possible applications in spintronics and nano electronic devices
A Research on Book Reading Habits of Turkish Teachers
Reading is the act of understanding and interpreting itself and its surroundings from the moment that human being is present. Therefore, individuals those who would like to know the environment better should have gained the reading habit. Turkish teachers are one of the effective factors in the acquisition of reading habits. It is necessary for the Turkish teachers who are role-models in every sense to be an example in reading books and encourage them. The purpose of this research is to examine the reading habits of Turkish teachers. In the study, the screening model was pursued with purpose of the determine the reading habits of Turkish teachers. As for that the sample of the research, is consist of 92 Turkish Teachers. By using easily accessible sampling method in the study, the teachers, who are on duty in these two countries, have been involved in the study. In order to collect data in the study, "Personal Information Form", where 4 questions about teachers 'personal information were prepared, and prepared "Reading Habit Form", which was used to describe teachers' reading habits, were being used. As a result of the study, it has been determined that Turkish teachers read regular books, have limited time to read daily books, prefer literary works to read frequently, do not follow any newspaper or magazine, and can not allocate the necessary budget for the book
New Approaches to the Evolution of Social Behavior
One of the most fascinating topics in evolutionary biology is how and why organisms cooperate with each other. Natural selection works through competition between alleles for representation in the next generation. Yet one sees everywhere organisms actually helping each other, from mutualisms between ants and plants to the altruistic acts of firefighters storming into burning buildings to rescue people. But how can natural selection lead to cooperation? This, of course, is not a new question, and a tremendous amount of work in evolutionary theory in the last 40 years has shown that helping others can frequently be the winning strategy in the struggle for existence. We have a sophisticated theory of social evolution, dealing not only with helping behaviors, but also other behaviors such as policing, spiteful harm-doing, and so on
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