We generalize the known collision results for a solid in a 3D compressible Newtonian fluid to compressible non-Newtonian ones, and to Newtonian fluids with temperature-depending viscosities.

This review essay focuses on electoral politics and the African accountability struggle, which has gained interest and scholarly attention following the third wave of democratization. Before the Namibia Constituent Assembly elections in November 1989, many would agree that elections were neither acknowledged nor considered appropriate for selecting governmental and national leaders. However, the democratic wave in the early 1990s marked a substantial political shift in Africa. Elections, once rare, are now frequent, serving as a crucial tool for both development and accountability. In this new era, citizens have a rare opportunity to hold their leaders accountable and exert control over their behavior. This review specifically addresses two volumes: Electoral Politics and Africa’s Urban Transition: Class and Ethnicity in Ghana by Noah L. Nathan and Elites and the Politics of Accountability in Africa, edited by Wale Adebanwi and Rogers Orock. Specifically, these volumes delve into topics concerning electoral politics and Africa’s challenges in achieving accountability.

How might we think queerly about the politics of performance in public space? Inspired by ‘queer’ as a straying from the straight-and-narrow and by the street as a site of chance meetings and awkward run-ins, I stage in this essay an encounter between two different approaches to thinking the politics of performance in public space. The first approach follows a familiar path: Bertolt Brecht's ‘street scene’ and Walter Benjamin's account of epic theatre. The second approach follows the walking performances of two queer migrant artists – South Korean-born Jisoo Yoo, now based in France, and Mozambican-born Jupiter Child, now based in Denmark – who interrogate the disorientation of the queer migrant body in Western European public space. Exploring the surprisingly busy intersection between the Brechtian street scene and the work of these two artists reveals a politics of performance in public space that favours orientation over rupture.

The article examines the role of children's magazines in promoting internationalism and solidarity in the German Democratic Republic (GDR). Analysing the magazines ABC-Zeitung, Bummi, and Frösi, it sheds light on their contribution to the GDR's system for collecting and distributing charitable donations and to cultivating children's commitment to countries in Africa, Asia, and Latin America. The article uncovers multifaceted layers of meaning associated with internationalism and emphasizes the significance of the connection between the state-ideological and the everyday levels. Its analysis of primary sources, including articles from the children's magazines, files from the Federal Archives, and historical publications, reveals that the magazines played a crucial role in fostering international solidarity and shaping the political consciousness of young readers. The use of techniques such as suggestion, competition, and renunciation in the magazines not only evoked a sense of collective responsibility, but also positioned children as active contributors to shaping an international socialist future. The children's magazine Bummi is particularly significant in the GDR's charitable donations system as it shows the involvement of other parts of society and thus raises issues of transgenerational education through the medium of children's magazines. By shifting away from the narrative of indoctrination, this article highlights the broader understanding of internationalism in the GDR and its integration into everyday life. It therefore underscores the vital role of children's magazines not only in fostering a stance of anti-imperialist solidarity among young readers, but also in shaping the GDR's vision of an international socialist future.

Scholars have long questioned whether and how courts influence society. We contribute to this debate by investigating the ability of judicial decisions to shape issue attention and affect toward courts in media serving the LGBTQ+ community. To do so, we compiled an original database of LGBTQ+ magazine coverage of court cases over an extended period covering major decisions, including Lawrence v. Texas (2003), Goodridge v. Massachusetts Department of Public Health (2003), and Lofton v. Secretary of Department of Children & Family Services (2004). We argue these cases influence the volume and tone of LGBTQ+ media coverage. Combining computational social science techniques with qualitative analysis, we find increased attention to same-sex marriage after the decisions in Lawrence, Goodridge, and Lofton, and the coalescence of discussions of courts around same-sex marriage after Lawrence. We also show how LGBTQ+ media informed readers about the political and legal implications of struggles over marriage equality.

Les inputs audiovisuels tels que les films et les séries sont de plus en plus souvent utilisés dans les cours de langue étrangère (LE) car ils permettent une exposition authentique à la langue. Plusieurs études suggèrent qu’ils soutiennent l’apprentissage de nouveaux mots, mais que l’inclusion d’activités de pré-/post-visionnage pourrait renforcer cet apprentissage. La présente étude a été menée en Suisse alémanique et s’intéresse à l’effet de la présence et du placement d’une telle activité sur l’apprentissage de 51 mots cibles. Dans une étude within-design, 97 apprenants de français langue étrangère de 13–14 ans ont regardé trois extraits de la série télévisée « Plan Cœur » (Netflix, 2018). Les trois conditions étaient : épisode seul, épisode et activité avant, épisode et activité après. Les activités portaient sur la reconnaissance du sens des mots cibles. Trois post-tests immédiats et un post-test différé du même type (reconnaissance de sens) ont été effectués auprès des quatre classes de niveau scolaire supérieur (classes générales et prégymnasiales/GPG) et des deux classes de niveau scolaire inférieur (classes à exigences de base/EBA). Nos résultats confirment la supériorité des conditions avec activité ainsi qu’une différence (peu surprenante) selon le niveau scolaire. On trouve aussi une interaction entre le moment de test et condition avec plus de réponses correctes aux post-tests immédiats. La différence entre activité pré et post est cependant négligeable. Ces résultats soulignent l’importance des activités pré-/post-visionnage pour l’apprentissage de nouveaux mots en LE.

Safe and socially compliant navigation in a crowded environment is essential for social robots. Numerous research efforts have shown the advantages of deep reinforcement learning techniques in training efficient policies, while most of them ignore fast-moving pedestrians in the crowd. In this paper, we present a novel design of safety measure, named Risk-Area, considering collision theory and motion characteristics of different robots and humans. The geometry of Risk-Area is formed based on the real-time relative positions and velocities of the agents in the environment. Our approach perceives risk in the environment and encourages the robot to take safe and socially compliant navigation behaviors. The proposed method is verified with three existing well-known deep reinforcement learning models in densely populated environments. Experiment results demonstrate that our approach combined with the reinforcement learning techniques can efficiently perceive risk in the environment and navigate the robot with high safety in the crowds with fast-moving pedestrians.

In this paper, we consider the following non-linear system involving the fractional Laplacian0.1

\begin{equation} \left\{\begin{array}{@{}ll} (-\Delta)^{s} u (x)= f(u,\,v), \\ (-\Delta)^{s} v (x)= g(u,\,v), \end{array} \right. \end{equation}

$0< s<1$

$x_n$

Mining operations in the Enmynveem valley, northeastern Siberia, exposed a well-preserved right hind leg of Mammuthus primigenius (woolly mammoth), dated to ca. 37,500 cal yr BP. The leg had a fracture that crosscut the midsections of the tibia and fibula. Additional skeletal and soft tissue remains, including two mummified adults (Berezovka, ca. 47,200 cal yr BP; Bolshoi Lyakhovsky, ca. 37,000 cal yr BP), document the presence of mammoths in interior mountain valleys and across both northern and southern coasts of far northeastern Siberia during Marine Isotope Stage (MIS) 3. A mosaic of herb-dominated tundra communities characterized the vegetation of the Enmynveem site during late to middle MIS 3 and MIS 2 (ca. 37,000–17,000 cal yr BP). Shrubs were limited to Salix during the late Pleistocene, whereas Betula also may have been present in sheltered sites during MIS 3. Herb communities remained dominant during the late Pleistocene–Early Holocene transition, although shrub Betula increased during this interval. By ca. 10,200 cal yr BP, the vegetation was Betula–Alnus shrub tundra. Larix and Pinus pumila were established in the valley by ca. 8700 cal yr BP and ca. 5700 cal yr BP, respectively.

Emotions shape strategic conflict dynamics. However, the precise way in which strategic and emotional concerns interact to affect international cooperation and contention are not well understood. We propose a model of intergroup conflict under incomplete information in which agents are sensitive to psychological motivations in the form of anger. Agents become angry in response to worse-than-expected outcomes due to actions of other players. Aggression may be motivated by anger or by beliefs about preferences of members of the other group. Increasing one group’s sensitivity to anger makes that group more aggressive but reduces learning about preferences, which makes the other group less aggressive in response to bad outcomes. Thus, anger has competing effects on the likelihood of conflict. The results have important implications for understanding the complex role of anger in international relations and, more generally, the interplay between psychological and material aims in both fomenting and ameliorating conflict.

Catholic education faces a number of serious challenges including cultural and political disrespect for, and hostility towards religion in general and Catholicism in particular, and lack of knowledge of, and commitment to, Catholic beliefs and values among Catholic educational administrators, school managers, teachers, and other staff, as well as the diminishing percentage of even nominally Catholic staff. I set these matters within the context of broader challenges surrounding Catholic education, deriving from three cultural movements: the reformation, the emergence of liberalism, and the scientific revolution, which undermined the synthesis of scripture, theology, and speculative and practical philosophy achieved in the high middle-ages. I propose in response a creative critique showing that what is of authentic value in modernity can be accommodated within the traditional synthesis. I also connect that tradition with strands of eastern philosophy suggesting that the movement of people, ideas, and traditions from Eastern cultures into historically Western societies provides an opportunity for further synthesis of a wisdom-based approach to education.

In the early 1970s, the plight of a charismatic Black American communist and philosophy professor Angela Davis, put on trial in the United States for her alleged involvement in a courtroom shootout in California, galvanized international public opinion. A massive publicity campaign in support of Angela Davis resonated across the globe and drew in millions of volunteers and sympathizers. The nations of the communist bloc, led by the Soviet Union, were particularly active in rallying their citizens in defense of a jailed American radical. In 1970–1972, Davis became a household name throughout the Soviet Union (but also in East Germany, Cuba, Poland, and other socialist nations). The “Free Angela Davis” campaign was unprecedented in scope and left a lasting mark on the collective memory of the citizens of the Soviet Union and its socialist satellites. Such was the impact of this propaganda juggernaut that decades later the image of Angela Davis remained current as a pop-cultural phenomenon across the former Soviet spaces and a symbol of unrealized and often conflicting aspirations towards freedom.

The article analyses the solidarity campaigns organized by the Czechoslovak Committee for Solidarity with African and Asian Peoples between the 1960s and 1980s. It situates the Czechoslovak solidarity towards African countries in the wider framework of the solidarity politics of the Eastern bloc and points out differences as well as similarities. Although the Czechoslovak Solidarity Committee was one of the first such committees to be founded in Eastern Europe, in the 1960s its official as well as public commitment to internationalist principles was modest compared with those of solidarity movements elsewhere in the bloc. However, the solidarity campaigns with African liberation movements intensified in the early 1970s. The campaigns in this period were marked by strong national symbolism, which drew on historical parallels between the African and Czechoslovak struggles for independence. The everyday internationalism in this case filled the public space with images of shared suffering, inferiority, and occupation, through which Czechoslovak citizens made sense of their historical role in the world. The article argues that this “nationalization” of official solidarity campaigns helped to embed the victimization narratives that survived the Velvet Revolution and that, in the 1990s, became a basis for new Czech and Slovak political identification.

This article examines the interplay between traditional leaders, democratically elected leaders and succession in Makapanstad Village, North West Province, South Africa. The article stems from community-based participatory action research conducted in Makapanstad in 2018. The article uses research data, in the form of community dialogue, together with desktop literature on the same subject. The article analyses the significance and role of traditional leadership in a democratic South Africa. It considers traditional leadership and democratically elected leadership in conjunction with succession and the demarcation of roles and responsibilities. The article analyses participants’ views to explore the form of leadership preferred by the residents of Makapanstad. It argues that, despite the recognition of traditional leadership in South Africa's Constitution, the roles and responsibilities of traditional leaders in local and provincial arms of government are limited, in contrast to those of democratically elected leaders.