Raman scattering study of bulk and nanocrystalline PbMoO4 at high pressures

High-pressure Raman scattering measurements have been performed in wulfenite (PbMoO4) for both bulk and nanocrystalline powders up to 22 GPa. Our Raman scattering measurements evidence the phase transition from the tetragonal scheelite structure to the monoclinic M-fergusonite structure in both bulk and nanocrystalline powders above 10.8 and 13.4 GPa, respectively. The pressure dependences of the Raman active modes in both structures were compared and discussed based on our theoretical results obtained from lattice dynamics ab initio calculations. © 2012 American Institute of Physics.Financial support from the Spanish ConsoliderIngenio 2010 Program (Project No. CDS2007-00045) is acknowledged. The work was also supported by Spanish MICINN under Projects MAT2010-21270-C04-01/03/04 and from Vicerrectorado de Investigacion de la Universitat Politecnica de Valencia under Projects UPV2011-0914PAID-05-11 and UPV2011-0914 PAID-05-11. 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Integrated social protection, inequity and COVID-19: rethinking Pacific community responses in Aotearoa

COVID-19 has forced us to think critically about alternative global and local response strategies to the unprecedented devastation. Some of the most infected groups are Pacific communities and this has raised concern about the need to seriously address the issue of health and socio-economic inequality. One way of doing this is through social protection. The paper critically examines some of the conventional notions of social protection, especially those predicated on market-imperatives and assumptions and argues for new and community-relevant innovative social protection strategies to effectively mitigate the effects of COVID-19. It then discusses the integrated social protection approach (ISPA), The paper argues that while ISPA is an attempt to create an alternative, inclusive and participatory social protection strategy, the issues of equity in terms of distribution of resources and power still need to be fully addressed because of their potential to cause tension within the community. The meaningful participation and empowerment of the Pacific communities and the strategic use of their cultural norms in social protection framing and implementation are important in building up resilience and sustainability to mitigate effectively against the sudden onset of pandemics such as COVID-19