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In this study, the effects of two different ammonium-exchange methods to improve the ammonia (NH3) gas adsorption of raw clinoptilolite (CLN) from Gördes (Türkiye) was investigated. The first method involved direct modification of CLN by 0.5 or 1.0 M NH4NO3 solutions at 80°C for 4 and 8 h followed by calcination. In the second method, CLN was converted to the Na+ form prior to modification with ammonium nitrate and calcination under the same conditions. Both methods yielded H+ forms of CLN through the removal of exchangeable cations without damaging the crystal structure. Ammonia adsorption isotherms were determined at 298 K for a total of eight different H+ forms synthetized using both methods. The Na-1.0-8h CLN sample with the highest NH3 adsorption capacity obtained using the second method was selected as the parent CLN. In addition, to determine the effects of doping different cations into the structure on the NH3 adsorption properties of the selected parent CLN sample, cation-exchange processes were carried out using 0.5 and 1.0 M NaNO3, KNO3, Ca(NO3)2 and Mg(NO3)2 solutions at 80°C for 4 h. The raw and modified CLNs were characterized using X-ray diffraction, X-ray fluorescence, scanning electron microscopy and N2 adsorption analyses. Cation-exchanged samples with a wide range of NH3 adsorption capacities (3.61–4.93 mmol g–1) were compared with other zeolites from the literature.
In June 1887, Britons crowded the streets of London to celebrate Queen Victoria's fiftieth year on the throne. It was an opportunity to publicly revel in the social, political, economic, and imperial progress Britain had made during her historic reign. The Lord Chamberlain was tasked with organizing a formal jubilee ceremony at Westminster Abbey representative of the queen's diverse subjects. But this proved a difficult undertaking for a multinational kingdom with a vast overseas empire. Grievances over seating in Westminster Abbey, jubilee honors, and an absent royal family fostered varying degrees of solidarity and rivalry among the United Kingdom's four constituent nations. The Irish Question and imperial expansion—matters in which Victoria was personally invested—heightened four-nations sensibilities and influenced participation in the festivities. The queen's Golden Jubilee both reflected and inspired four-nations thinking, and it revealed public concerns that the British union might exist as a hierarchy of nations rather than as a collaborative venture among equal members. As the institutional embodiment of tiered society, the Crown became an outlet for subjects to explore questions and modes of belonging within the global British world. A four-nations analysis of Victoria's 1887 jubilee shows that despite its unifying function, the modern British monarchy has struggled to harmonize the United Kingdom's multinational perspectives.
The significance of food is beyond its gastronomic value. Food symbolises a community's enriched past and holds cultural expressions and traditional knowledge. The linkage of food with religious beliefs, geo-climatic factors, social standards, and various health benefits builds the reputation of the food, which is essentially attributable to its geographic origin. Following the ratification of the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS), the contracting states that have enacted Geographical Indications (GI) legislation (particularly those in Asia) have come forward to protect foodstuffs as GI in order to safeguard their communities and their traditional knowledge associated with foodstuffs. Against this background, the present article attempts to compare foodstuff GIs in eight selected Asian countries with a sui generis system of GI protection as TRIPS compliance. The comparative analysis of the evolution and scope of foodstuff protection, pre-registration and post-registration impact, and quality maintenance provides important insights into convergence and divergence among the selected Asian countries. The study further identifies policy implications for the sustenance of GI.
Supersonic backward-facing step (BFS) flow is numerically studied using direct numerical simulation (DNS) and global stability analysis (GSA) with a free stream Mach number of 2.16 and a Reynolds number of 7.938 × 105 based on the flat-plate length L and free stream conditions. Two-dimensional BFS flow becomes unstable to three-dimensional perturbations as the step height h exceeds a certain value, while no two-dimensionally unstable mode is found. Global instability occurs with the fragmentation of the primary separation vortex downstream of the step. Two stationary modes and one oscillatory unstable mode are obtained at a supercritical ratio of L/h = 32.14, among which the two stationary modes originate from the coalescence of a pair of conjugate modes. The most unstable mode manifests itself as streamwise streaks in the reattached boundary layer, which is similar to that in shock-induced separated flow, although the flow separation mechanisms are different. Without introducing any external disturbances, the DNS captures the preferred perturbations and produces a growth rate in agreement with the GSA prediction in the linear growth stage. In the quasi-steady stage, the secondary separation vortex breaks up into several small bubbles, and the number of streamwise streaks is doubled. A low-frequency unsteadiness that may be associated with the oscillatory mode is also present.
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.
Elasto-inertial turbulence (EIT) is a recently discovered two-dimensional chaotic flow state observed in dilute polymer solutions. Two possibilities are currently hypothesized to be linked to the dynamical origins of EIT: (i) viscoelastic Tollmien–Schlichting waves and (ii) a centre-mode instability. The nonlinear evolution of the centre mode leads to a travelling wave with an ‘arrowhead’ structure in the polymer conformation, a structure also observed instantaneously in simulations of EIT. In this work we conduct a suite of two-dimensional direct numerical simulations spanning a wide range of polymeric flow parameters to examine the possible dynamical connection between the arrowhead and EIT. Our calculations reveal (up to) four coexistent attractors: the laminar state and a steady arrowhead regime (SAR), along with EIT and a ‘chaotic arrowhead regime’ (CAR). The SAR is stable for all parameters considered here, while the final pair of (chaotic) flow states are visually very similar and can be distinguished only by the presence of a weak polymer arrowhead structure in the CAR regime. Analysis of energy transfers between the flow and the polymer indicates that both chaotic regimes are maintained by an identical near-wall mechanism and that the weak arrowhead does not play a role. Our results suggest that the arrowhead is a benign flow structure that is disconnected from the self-sustaining mechanics of EIT.
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.
Medical professionals can use mass-casualty triage systems to assist them in prioritizing patients from mass-casualty incidents (MCIs). Correct triaging of victims will increase their chances of survival. Determining the triage system that has the best performance has proven to be a difficult question to answer. The Advanced Prehospital Triage Model (Modelo Extrahospitalario de Triaje Avanzado; META) and Sort, Assess, Lifesaving Interventions, Treatment/Transport (SALT) algorithms are the most recent triage techniques to be published. The present study aimed to evaluate the META and SALT algorithms’ performance and statistical agreement with various standards. The secondary objective was to determine whether these two MCI triage systems predicted patient outcomes, such as mortality, length-of-stay, and intensive care unit (ICU) admission.
Methods:
This retrospective study used patient data from the trauma registry of an American College of Surgeons Level 1 trauma center, from January 1, 2018 through December 31, 2020. The sensitivity, specificity, and statistical agreement of the META and SALT triage systems to various standards (Revised Trauma Score [RTS]/Sort Triage, Injury Severity Score [ISS], and Lerner criteria) when applied using trauma patients. Statistical analysis was used to assess the relationship between each triage category and the secondary outcomes.
Results:
A total of 3,097 cases were included in the study. Using Sort triage as the standard, SALT and META showed much higher sensitivity and specificity in the Immediate category than for Delayed (Immediate sensitivity META 91.5%, SALT 94.9%; specificity 60.8%, 72.7% versus Delayed sensitivity 28.9%, 1.3%; specificity 42.4%, 28.9%). With the Lerner criteria, in the Immediate category, META had higher sensitivity (77.1%, SALT 68.6%) but lower specificity (61.1%) than SALT (71.8%). For the Delayed category, SALT showed higher sensitivity (META 61.4%, SALT 72.2%), but lower specificity (META 75.1%, SALT 67.2%). Both systems showed a positive, though modest, correlation with ISS. For SALT and META, triaged Immediate patients tended to have higher mortality and longer ICU and hospital lengths-of-stay.
Conclusion:
Both META and SALT triage appear to be more accurate with Immediate category patients, as opposed to Delayed category patients. With both systems, patients triaged as Immediate have higher mortality and longer lengths-of-stay when compared to Delayed patients. Further research can help refine MCI triage systems and improve accuracy.
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}
in two different types of domains, one is bounded, and the other is an infinite cylinder, where $0< s<1$. We employ the direct sliding method for fractional Laplacian, different from the conventional extension and moving planes methods, to derive the monotonicity of solutions for (0.1) in $x_n$ variable. Meanwhile, we develop a new iteration method for systems in the proofs. Hopefully, the iteration method can also be applied to solve other problems.
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.
In this article, the authors present an analysis of radiocarbon dates from a stratified deposit at the Greek Geometric period settlement of Zagora on the island of Andros, which are among the few absolute dates measured from the period in Greece. The dates assigned to Greek Geometric ceramics are based on historical and literary evidence and are found to contradict absolute dates from the central Mediterranean which suggest that the traditional dates are too young. The results indicate the final period at Zagora, the Late Geometric, should be seen as starting at least a century earlier than the traditional date of 760 BC.
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.