Titanium offers a burgeoning isotope system that has shown significant promise as a tracer of magmatic processes. Recent studies have shown that Ti displays significant massdependent variations linked to the crystallisation of Fe-Ti oxides during magma differentiation.We present a comprehensive set of Ti isotope data for a range of differentiation suites from alkaline (Ascension Island, Afar and Heard Island), calc-alkaline (Santorini) and tholeiitic (Monowai seamount and Alarcon Rise) magma series to further explore the mechanics of Ti isotope fractionation in magmas. Whilst all suites display an increase in 49/47 Ti (deviation in 49 Ti/ 47 Ti of a sample relative to the OL-Ti reference material) during magma differentiation relative to indices such as increasing SiO 2 and decreasing Mg#, our data reveal that each of the three magma series have contrasting 49/47 Ti fractionation patterns over comparable ranges of SiO 2 and Mg#. Alkaline differentiation suites from intraplate settings display the most substantial range of variation ( 49/47 Ti = +0.01 to +2.32 ), followed by tholeiites (-0.01 to +1.06 ) and calc-alkaline magmas (+0.06 to +0.64 ). Alkaline magmas possess high initial melt TiO 2 contents which enables early saturation of ilmenite + titanomagnetite and a substantial degree of oxide crystallisation, whereas tholeiitic and calc-alkaline suites crystallise less oxide and have titanomagnetite as the dominant oxide phase. Positive slopes of FeO*/TiO 2 vs. SiO 2 during magma differentiation are related to high degrees of crystallisation of Ti-rich oxides (i.e. ilmenite). Bulk solid-melt Ti isotope fractionation factors co-vary with the magnitude of the slope of FeO*/TiO 2 vs. SiO 2 during magma differentiation, this indicates that the modal abundance and composition of the Fe-Ti oxide phase assemblage, itself is controlled by melt composition, governs Ti isotope fractionation during magma evolution. In addition to this overall control, hydrous, oxidised calc-alkaline suites display a resolvable increase in 49/47 Ti at higher Mg# relative to drier and more reduced tholeiitic arc suites. These subparallel Ti isotope fractionation patterns are best explained by the earlier onset of oxide segregation in arc magmas with a higher oxidation state and H 2 O content. This indicates the potential of Ti isotopes to be utilised as proxies for geodynamic settings of magma generation.

The trade union journal has never attracted much attention—the primary object of this article is to review the production and distribution and the changes which have taken place in these during the past two decades.

Within international relations theorizing, political leaders are rarely cast as norm entrepreneurs or change agents. As heads of government, they have their own sources of legitimacy and authority, but also significant constraints. This article, based on new archival research, adds nuance to this model by exploring the leadership roles of Franklin Roosevelt and Harry Truman on influencing global views on refugee protection. The role both presidents played at the international level was moderated by constraints at the domestic level within the congressional and executive branches. While both presidents demonstrated a strong commitment to refugees, only Truman was able to bring about change in U.S. policy by deploying the tools of norm entrepreneurship.Are elite decision makers, such as the president, norm entrepreneurs? Within international relations constructivist theorizing, norm entrepreneurs are seen as critical to the early stages of norm emergence, where norms are defined as shared understandings of appropriate behavior for actors with a given identity that isolates a single strand of behavior (Jepperson, Wendt, and Katzenstein 1996, 52; see also Finnemore and Sikkink 1998, 891). These entrepreneurs hold strong notions about appropriate or desirable behavior Phil Orchard is a senior lecturer in international relations and peace and conflict studies at the University of Queensland and the research of the Asia-Pacific Centre for the Responsibility to Protect. His research focuses on international efforts to provide institutional and legal protection to civilians and forced migrants. He

Canada has been relatively immune to grassroots-driven populist political forces in recent years despite global shifts toward a mainstreaming of nationalist identity-driven politics. The coronavirus disease 2019 (COVID-19) pandemic coupled with other shifts in the Canadian and international political landscapes, have changed this dynamic. This article takes interest in the 2022 Freedom Convoy—also known as Convoi de la liberté in French—through the lens of Canadian political as well as science and health-based communication. The protesters’ actions, and the subsequent political response, suggest an increased political entanglement with both protest movements and identity-driven political communications and messaging.

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