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We report a new design of polymer-patched gold nanoparticles (AuNPs) with controllable interparticle interactions in terms of their direction and strength. Patchy AuNPs (pAuNPs) are prepared through hydrophobicity-driven surface dewetting under deficient ligand exchange conditions. Using the exposed surface on pAuNPs as seeds, a highly controllable growth of AuNPs is carried out via seed-mediated growth while retaining the size of polymer domains. As guided by ligands, these pAuNPs can self-assemble directionally in two ways along the exposed surface (head-to-head) or the polymer-patched surface of pAuNPs (tail-to-tail). Control of the surface asymmetry/coverage on pAuNPs provides an important tool in balancing interparticle interactions (attraction vs. repulsion) that further tunes assembled nanostructures as clusters and nanochains. The self-assembly pathway plays a key role in determining the interparticle distance and therefore plasmon coupling of pAuNPs. Our results demonstrate a new paradigm in the directional self-assembly of anisotropic building blocks for hierarchical nanomaterials with interesting optical properties. 

Abstract Objectives Later adult work attachments and exits are in flux, suggesting the need for understanding both the range of contemporary population-level pathways of work and non-work and variations by overlapping social locations. We document patterned continuity and change in monthly work attachments and analyze the intersecting effects of age, gender, education, and race/ethnicity. Methods We capitalize on massive micro-level 16-month panel data from the Current Population Survey (CPS) from 2008 through 2016 to empirically identify patterned pathways of monthly states: working full time, long hours, part time; being self-employed or unemployed; not working because of a disability, due to family care or other reasons, or because one defines oneself as retired. Results Analyses of 346,488 American women and men ages 50 to 75 reveal patterned elasticity in the timing and nature of work attachments in the form of six distinctive pathways. Our intersectional analyses illustrate divergences and disparities: advantages for educated white men, disadvantages for low-educated Black men and women through their early 60s, and intersecting effects of gender, education, and race/ethnicity during the later work course across age groups. We find convergence across social markers by the 70s. Discussion This research highlights the importance of intersectional analysis, recasting the gendered work course in later adulthood into a framework of even greater complexities within mutually shaping categories of race/ethnicity, class, and age. Older Americans experience patterned, uneven pathways around work and non-work. We recommend additional scholarship on the dynamics of constrained and disparate choices unfolding across multiple intersecting social locations. 

Service robots often perform their main functions in public settings, interacting with more than one person at a time. How these robots should handle the affairs of individual users while also behaving appropriately when others are present is an open question. One option is to design for flexible agent embodiment: letting agents take control of different robots as people move between contexts. Through structured User Enactments, we explored how agents embodied within a single robot might interact with multiple people. Participants interacted with a robot embodied by a singular service agent, agents that re-embody in different robots and devices, and agents that co-embody within the same robot. Findings reveal key insights about the promise of re-embodiment and co-embodiment as design paradigms as well as what people value during interactions with service robots that use personalization.