392 research outputs found

    Particulate lubricants in cosmetic applications

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    Polymer powders are commonly added to cosmetic formulations to improve product performance and skin feel. This study investigates the effect of particle concentration and size on the lubricating properties of powder suspensions. Results are reported for various particle sizes and concentrations. When the tribological contact was fully immersed the addition of particles had no effect. However different behaviour was observed when the contact was only partially lubricated. In this case, a three-stage friction coefficient curve was observed. By varying the particle size and concentration it was shown that the duration and magnitude of each stage can be controlled

    Towards a skin-on-a-chip for screening the dermal absorption of cosmetics

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    Over the past few decades, there have been increasing global efforts to limit or ban the use of animals for testing cosmetic products. This ambition has been at the heart of international endeavours to develop new in vitro and animal-free approaches for assessing the safety of cosmetics. While several of these new approach methodologies (NAMs) have been approved for assessing different toxicological endpoints in the UK and across the EU, there remains an absence of animal-free methods for screening for dermal absorption; a measure that assesses the degree to which chemical substances can become systemically available through contact with human skin. Here, we identify some of the major technical barriers that have impacted regulatory recognition of an in vitro skin model for this purpose and propose how these could be overcome on-chip using artificial cells engineered from the bottom-up. As part of our future perspective, we suggest how this could be realised using a digital biomanufacturing pipeline that connects the design, microfluidic generation and 3D printing of artificial cells into user-crafted synthetic tissues. We highlight milestone achievements towards this goal, identify future challenges, and suggest how the ability to engineer animal-free skin models could have significant long-term consequences for dermal absorption screening, as well as for other applications

    Varieties of Limited Access Orders: The nexus between politics and economics in hybrid regimes

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    This article advances our understanding of differences in hybrid stability by going beyond existing regime typologies that separate the study of political institutions from the study of economic institutions. It combines the work of Douglass North, John Wallis, and Barry Weingast (NWW) on varieties of social orders with the literature on political and economic regime typologies and dynamics to understand hybrid regimes as Limited Access Orders (LAOs) that differ in the way dominant elites limit access to political and economic resources. Based on a measurement of political and economic access applied to seven post‐Soviet states, the article identifies four types of LAOs. Challenging NWW's claim, it shows that hybrid regimes can combine different degrees of political and economic access to sustain stability. Our typology allows to form theoretical expectations about the kinds of political and/or economic changes that will move different types of LAOs toward more openness or closure

    Foreign Direct Investments in Business Services: Transforming the VisegrΓ‘d Four Region into a Knowledge-based Economy?

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    Foreign direct investments (FDIs) in the service sector are widely attributed an important role in bringing more skill-intensive activities into the Visegrad Four (V4). This regionβ€”comprising Poland, the Czech Republic, Hungary and Slovakiaβ€”relied heavily on FDIs in manufacturing, which was often found to generate activities with limited skill content. This contribution deconstructs the chaotic concept of β€œbusiness services” by analysing the actual nature of service sector activities outsourced and offshored to the V4. Using the knowledge-based economy (KBE) as a benchmark, the paper assesses the potential of service sector outsourcing in contributing to regional competitiveness by increasing the innovative capacity. It also discusses the role of state policies towards service sector FDI (SFDI). The analysis combines data obtained from case studies undertaken in service sector outsourcing projects in V4 countries. Moreover, it draws on interviews with senior employees of investment promotion agencies and publicly available data and statistics on activities within the service sector in the region. It argues that the recent inward investments in business services in the V4 mainly utilize existing local human capital resources, and their contribution to the development of the KBE is limited to employment creation and demand for skilled labour

    Crisis and change in industrial relations in Central and Eastern Europe

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    This article introduces the special issue on industrial relations in Central and Eastern Europe since the financial and economic crisis. Already dependent economically on funding from the west, and lacking the robust industrial relations institutions traditional in much of Western Europe, countries in the region were particularly vulnerable. However, there are important cross-national differences, and the strategies of key actors have significantly affected the outcomes

    PAK1 modulates a PPARΞ³/NF-ΞΊB cascade in intestinal inflammation

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    P21-activated kinases (PAKs) are multifunctional effectors of Rho GTPases with both kinase and scaffolding activity. Here, we investigated the effects of inflammation on PAK1 signaling and its role in colitis-driven carcinogenesis. PAK1 and p-PAK1 (Thr423) were assessed by immunohistochemistry, immunofluorescence, and Western blot. C57BL6/J wildtype mice were treated with a single intraperitoneal TNFΞ± injection. Small intestinal organoids from these mice and from PAK1-KO mice were cultured with TNFΞ±. NF-ΞΊB and PPARΞ³ were analyzed upon PAK1 overexpression and silencing for transcriptional/translational regulation. PAK1 expression and activation was increased on the luminal intestinal epithelial surface in inflammatory bowel disease and colitis-associated cancer. PAK1 was phosphorylated upon treatment with IFNΞ³, IL-1Ξ², and TNFΞ±. In vivo, mice administered with TNFΞ± showed increased p-PAK1 in intestinal villi, which was associated with nuclear p65 and NF-ΞΊB activation. p65 nuclear translocation downstream of TNFΞ± was strongly inhibited in PAK1-KO small intestinal organoids. PAK1 overexpression induced a PAK1–p65 interaction as visualized by co-immunoprecipitation, nuclear translocation, and increased NF-ΞΊB transactivation, all of which were impeded by kinase-dead PAK1. Moreover, PAK1 overexpression downregulated PPARΞ³ and mesalamine recovered PPARΞ³ through PAK1 inhibition. On the other hand PAK1 silencing inhibited NF-ΞΊB, which was recovered using BADGE, a PPARΞ³ antagonist. Altogether these data demonstrate that PAK1 overexpression and activation in inflammation and colitis-associated cancer promote NF-ΞΊB activity via suppression of PPARΞ³ in intestinal epithelial cells

    Defending the genome from the enemy within:mechanisms of retrotransposon suppression in the mouse germline

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    The viability of any species requires that the genome is kept stable as it is transmitted from generation to generation by the germ cells. One of the challenges to transgenerational genome stability is the potential mutagenic activity of transposable genetic elements, particularly retrotransposons. There are many different types of retrotransposon in mammalian genomes, and these target different points in germline development to amplify and integrate into new genomic locations. Germ cells, and their pluripotent developmental precursors, have evolved a variety of genome defence mechanisms that suppress retrotransposon activity and maintain genome stability across the generations. Here, we review recent advances in understanding how retrotransposon activity is suppressed in the mammalian germline, how genes involved in germline genome defence mechanisms are regulated, and the consequences of mutating these genome defence genes for the developing germline
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