The response of a metapopulation to a changing environment

A species distributed across heterogeneous environments may adapt to local conditions. Szep et al. (2021, Evolution) modelled this process in the infinite island model, finding the stationary distribution of allele frequencies and deme sizes. We extend this to ask how a metapopulation responds to changes in carrying capacity, selection strength, or migration rate, restricting attention to fixed deme size ("soft selection"). We develop a "fixed-state" approximation (accurate when migration is rare) which assumes that the loci are near fixation. Under this approximation, polymorphism is only possible for a narrow range of habitat proportions when selection is weak compared to drift, but for a much wider range otherwise. When local conditions (Ns or Nm) change in a single deme, it takes a time of ~1/m to reach the new equilibrium. However, even withmany loci, there can be substantial fluctuations in net adaptation, due to the bimodal allele frequency distributions at each locus. Thus, in a finite metapopulation, variation may gradually be lost by chance, even if it would persist with infinitely many demes. When conditions change across the whole metapopulation, there can be rapid response, accurately predicted by the fixed-state approximation when Nm <<1.

National Minorities in the Western Borderlands of Czech Silesia from the Perspective of State Security Corps in 1945

In May 1945, Western Silesia, originally inhabited predominantly by the German population, found itself in a completely new situation. The region was once again controlled by the Czechoslovak state power, which wanted to re-organise life in the borderlands. Therefore, it was necessary to handle the issue of the German population, as well as the influx of new settlers from the Czechoslovak inland and abroad. Changes took place on the other side of the border as well, and neighbouring Germany was replaced by Poland. These aspects gave rise to a completely new security situation that the newly formed security corps had to address. The article attempts to follow the relationship of the Czechoslovak security corps to the members of other nationalities who lived in the researched area or with those whom they came into contact while guarding the non-fixed state borders. Research shows that, in 1945, the National Security Corps (SNB) indeed took qualitatively different approaches to various nationalities, ranging from strong hostility and distrust towards the Germans, through vigilance towards the Polish, to an ambiguous attitude towards re-emigrants.

The Tyrant’s Progress: The Meaning of ΤΥΡΑΝΝΟΣ in Plato and Aristotle

This article considers a longstanding problem: what does the word τύραννος mean? And if it means ‘bad / tyrannical ruler’, why are good rulers called tyrants? The solution proposed here is that tyranny is not a fixed state of being, or not being, but instead a gradual process of development. To be called a tyrant, a ruler need not embody all the stereotypical traits of tyranny. If tyranny is, by definition, unconstitutional and illegitimate rule, then there may be no clear moment at which one ceases to be a general or king and becomes a tyrant, only a process by which the tyrant gradually strengthens his rule and develops the negative attributes associated with absolute and illegitimate power. A strong trend in not only the political theory of Plato and Aristotle, but also Greek poetry and historiography in general, is to trace the decline of tyrannies from initially good and popular governments to ones that are despotic and unpopular: the tyrant’s progress.

Exploring Bullying: Fifth Graders’ Interpretations and Understandings

This study explored understandings shared by fifth-grade gifted students as they read the book Restart, which explores bullying. Students read, created representations, and discussed the text. Grounded by Langer’s stances of envisionment, this descriptive case study analyzed student representations and conversations. Each of the stances was represented with most responses being represented in Stances 1 (getting a sense of the text), 2 (interpreting text), and 4 (analyzing the text). In addition, most students viewed bullies and their behavior as being in a fixed state, which was tied to the perceived power a bully held. The results from this study have implications for teachers who work with gifted and talented students, counselors who work with students in mental health and resilience programs, and the collaboration of these school personnel.

The Effects of Fibular Malrotation on Tibiotalar Contact Area and Peak Pressure Distributions in Weber B Ankle Fractures

Category: Basic Sciences/Biologics; Ankle; Hindfoot; Trauma Introduction/Purpose: Decreased tibiotalar joint contact area (CA) and increased peak pressure (PP) following rotational ankle fractures may predispose the development of post-traumatic osteoarthritis. Previous studies have highlighted the effects of lateral talar translation on tibiotalar joint congruity. However, debate remains regarding surgical indications in minimally displaced (< 2mm of clear space widening), but potentially malrotated ankle fractures. Malrotation of the talus and fibula are poorly visualized on plain radiographs, thus their impact on ankle joint contact mechanics has not been determined. The aim of this project is to understand the effects of fibular malrotation on tibiotalar joint CA and PP distributions using an axially loaded cadaveric model. We hypothesized that fibular malrotation would result in decreased contact area and increased peak pressures within the tibiotalar joint. Methods: Ten fresh frozen cadaveric lower extremity specimens transected mid-tibia were dissected free of soft tissues surrounding the ankle, sparing the ligaments. The proximal tibia and fibula were potted in quick drying cement for rigid mounting on a MTS machine. A pressure sensing element (TekScan model 5033) was inserted into the tibiotalar joint and used to measure CA (cm2) and PP (MPa). An axial load of 686 N was applied through the tibia and fibula, followed by a 147 N load via the Achillies tendon at mid-stance position, 15o dorsiflexion and 15o plantarflexion. The samples were first tested in the native condition, a Weber B ankle fracture was simulated and then re-tested in an anatomically fixed state, and a malrotated state. Malrotation was achieved by externally rotating the talus and shortening the fibula along the fracture by the maximal amount that would allow bony apposition along the fracture line (usually 5-10mm). Results: In the six ankles tested thus far (Figure 1), we have observed small but statistically insignificant (P>0.05) increases in tibiotalar CA at all stance phases following malreduction. Significant (p>0.05) increases in tibiotalar PP were seen mid-stance following a simulated Weber B fracture, and these changes were shown to be greatest in the malreduced state versus the anatomically fixed state (7.21 MPa vs. 6.35 MPa respectively, p = 0.004). Interestingly, similar (p=0.84) decreases tibiotalar PP were shown during plantarflexion following a simulated Weber B fracture fixed in both the anatomically fixed and malreduced state. Conclusion: Our preliminary data supports the notion that significant changes in tibiotalar PP occur following ankle fractures even in an anatomically fixed state. Increases in tibiotalar PP seem to be further amplified following malreduction at specific stance phases. Further data collection is needed to validate these findings, and to determine the role of malrotation as a potential surgical indication for minimally laterally displaced ankle fractures.

What Next? Shostakovich's Sixth Symphony as Sequel and Prequel

For Dmitri Shostakovich, reaching the heights of the Soviet musical establishment proved easier than staying there. He triumphed with his Fifth Symphony of 1937, which marked the composer's return to official favour after the denunciation of his second opera and third ballet. Following that success, Shostakovich faced the problem of the sequel: whether or not, in the Sixth Symphony, to repeat, refute, or re-inscribe. I propose Shostakovich first thought about going big with his new project, composing a grand text-based score about Lenin, and then considered going small, grounding the first movement in folk fare and mixing light genres in the others. But in the end, he chose a more experimental approach. The Sixth Symphony collapses boundaries, both semantic and syntactic, pulling them back from a fixed state into a play of possibilities.

Currencies Cannot Change

Something I no longer believe is that size will always be the currency of the news media environment. Traditionally, the goal of most publications has been to reach as large an audience as possible. I assumed this was a fixed state of affairs, which resulted in other, smaller assumptions implicit within my research. When I first started studying the news industry, for example, I assumed the advent of sophisticated measures of online audience behavior would finally provide news publishers the answer to the question, “How do we reach as many people as possible?” I was similarly sure that the implications of this development would be profound: journalism would become more democratic, since editors would now know with certainty what subjects were of interest to their readers. On the other hand, journalism would become more focused on cat videos and celebrity gossip as audience analytic data made it plain that these types of content were most likely to attract the largest number of readers. Even as journalism stakeholders have begun talking more about “engagement” metrics, I have tended to assume these would complement, rather than replace, measures of audience size. Recently, however, the news industry has moved further away from the traditional, advertising-supported revenue model that privileges measures of audience size toward audience-supported models that privilege traits like loyalty. Though I remain unsure where these developments will ultimately lead, I am increasingly open-minded to the notion that currencies—like everything else in the news media environment—can change.

8. Selfhood and personality

‘Selfhood and personality: the psychology of identity’ considers how psychology deals with the question ‘Who am I?’. Rather than a fixed state, personal identity is an ongoing project. The individual forms his or her identity by identifying with someone or something. Individuals who are unable to reconcile competing personal and social demands may suffer an identity crisis, an experience once associated with adolescence, which, however, in recent decades has been linked to mental troubles in adult life stages, too. Personal identity is something we are, something we have, and something we act. We perform acts of identity following culture-specific stage directions that leave room for individual expressivity.