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Laser powder bed fusion (LPBF) in-situ alloying is a recently developed technology that provides a facile approach to optimizing the microstructural and compositional characteristics of the components for high performance goals. However, the complex mass and heat transfer behavior of the molten pool results in an inhomogeneous composition distribution within the samples fabricated by LPBF in-situ alloying. The study aims to investigate the heat and mass transfer behavior of an in-situ alloyed molten pool by developing a three-dimensional transient thermal-flow model that couples the metallurgical behavior of the alloy, thereby revealing the formation mechanism of composition inhomogeneity.

A multispecies multiphase computational fluid dynamic model was developed with thermodynamic factors derived from the phase diagram of the selected alloy system. The characteristics of the Al/Cu powder bed in-situ alloying process were investigated as a benchmark. The metallurgical behaviors including powder melting, thermal-flow, element transfer and solidification were investigated.

The Peclet number indicates that the mass transfer in the molten pool is dominated by convection. The large variation in material properties and temperature results in the presence of partially melted Cu-powder and pre-solidified particles in the molten pool, which further hinder the convection mixing. The study of simulation and experiment indicates that optimizing the laser energy input is beneficial for element homogenization. The effective time and driving force of the convection stirring can be improved by increasing the volume energy density.

This study provides an in-depth understanding of the formation mechanism of composition inhomogeneity in alloy fabricated by LPBF in-situ alloying.

Democratic renewal in Sri Lanka as well as a cross the Global South depends on strengthening democratic social movements within varieties of patrimonial capitalism. Patrimonial capitalism, emphasising patron–client relations, coincide with weakening democratic institutional cultures and practices. The dominant corruption/anti-corruption narrative is bracketed with elite class strategies aimed at negotiating a ‘managed corruption’. The realm of representative politics creating consent for patrimonial capitalism is shaped by: ethnic and class relations; the weakening of working-class parties; patriarchal cultures within parties; links with criminal networks; opaque finances and the integration of mainstream media with party patronage.

Democratising the realm of representative politics points towards democratic social movements. The internal dynamics of social movements, their relationships with political parties and collective learning are significant factors that shapes the strategic orientation of social movements. State repression of social movements highlights the need for demilitarisation and the abolition of prisons. The global sense of this local struggle relates to transforming financial markets and platform economies towards notions of financial and digital commons. The integration of different realms of politics, such as representative, movement, life and emancipatory politics, is vital for reinforcing solidarity as the basis for counter-hegemonic struggles.

Participatory budgeting's (PB’s) proponents hope that bringing development projects to historically underserved communities will improve well-being by extending infrastructure and services. This article details the logic connecting PB to well-being, describes the evolution of PB programs as they spread around the world and consolidates global evidence from research that tests hypotheses on PB's impact. The purpose of this paper is to address these issues.

Unstructured literature review and comparative case study across five global regions.

The authors find evidence for PB's impact on well-being in several important contexts, mostly not only in Brazil, but also in Peru and South Korea. They also find that very few rigorous, large-N, comparative studies have evaluated the relationship between PB and well-being and that the prospects for social accountability and PB's sustainability for well-being are not equally strong in all contexts. They argue that PB has great potential to improve well-being, but program designs, operational rules and supporting local conditions must be favorable to realize that potential.

This is one of the few efforts to build theory on where and why the authors would expect to observe relationships between PB and well-being. It is also one of the first to consolidate global evidence on PB's impact.

This study employs Stein Rokkan's methodological approach to analyse state formation in the Greater Middle East. It develops a conceptual framework distinguishing colonial, populist and democratic pacts, suitable for analysis of state formation and nation-building through to the present period. The framework relies on historical institutionalism. The methodology, however, is Rokkan's. The initial conceptual analysis also specifies differences between European and the Middle Eastern state formation processes. It is followed by a brief and selective discussion of historical preconditions. Next, the method of plotting singular cases into conceptual-typological maps is applied to 20 cases in the Greater Middle East (including Afghanistan, Iran and Turkey). For reasons of space, the empirical analysis is limited to the colonial period (1870s to the end of World War 1). Three typologies are combined into one conceptual-typological map of this period. The vertical left-hand axis provides a composite typology that clarifies cultural-territorial preconditions. The horizontal axis specifies transformations of the region's agrarian class structures since the mid-19th century reforms. The right-hand vertical axis provides a four-layered typology of processes of external intervention. A final section presents selected comparative case reconstructions. To the authors' knowledge, this is the first time such a Rokkan-style conceptual-typological map has been constructed for a non-European region.

The political crisis related to two main factors internal to the public revenue system, namely financial markets and the commercialisation of the state, and three related external factors, pertaining to the pandemic, popular discontent and inequality. The emphasis on financial markets since the mid-1990s expanded the commercialisation of the state while neglecting public accountability and government oversight. The efforts to shore up public finances through the tax system is increasingly undermined by the global tax architecture, enabling financial secrecy and illicit financial flows.

The pandemic revealed the significance of women’s work, paid as well as unpaid care work. The pandemic also exposed the limitations of a domestic economy, based on export-oriented development, over-reliant on tourism and remittances from migrant workers. Combining with the on-going dengue epidemic, the pandemic highlighted the urgency of climate adaptation. Meanwhile, the popular discontent conveyed an accumulation of grievances linked with cultural discrimination, political misrepresentation as well as economic maldistribution. The participation of new middle-class segments in the protests foregrounded new tendencies significant for strengthening the labour movement as well as working-class parties in their demands for redistribution, reframing democracy as well as citizenship.