When metal nanoparticles are arranged in an ordered array, they may scatter light to produce diffracted waves. If one of the diffracted waves then propagates in the plane of the array, it may couple ...the localized plasmon resonances associated with individual nanoparticles together, leading to an exciting phenomenon, the drastic narrowing of plasmon resonances, down to 1–2 nm in spectral width. This presents a dramatic improvement compared to a typical single particle resonance line width of >80 nm. The very high quality factors of these diffractively coupled plasmon resonances, often referred to as plasmonic surface lattice resonances, and related effects have made this topic a very active and exciting field for fundamental research, and increasingly, these resonances have been investigated for their potential in the development of practical devices for communications, optoelectronics, photovoltaics, data storage, biosensing, and other applications. In the present review article, we describe the basic physical principles and properties of plasmonic surface lattice resonances: the width and quality of the resonances, singularities of the light phase, electric field enhancement, etc. We pay special attention to the conditions of their excitation in different experimental architectures by considering the following: in-plane and out-of-plane polarizations of the incident light, symmetric and asymmetric optical (refractive index) environments, the presence of substrate conductivity, and the presence of an active or magnetic medium. Finally, we review recent progress in applications of plasmonic surface lattice resonances in various fields.
Progression of fibrosis involves interstitial hypercellularity, matrix accumulation, and atrophy of epithelial structures, resulting in loss of normal function and ultimately organ failure. There is ...common agreement that the fibroblast/myofibroblast is the cell type most responsible for interstitial matrix accumulation and consequent structural deformations associated with fibrosis. During wound healing and progressive fibrotic events, fibroblasts transform into myofibroblasts acquiring smooth muscle features, most notably the expression of alpha-smooth muscle actin and synthesis of mesenchymal cell-related matrix proteins. In renal disease, glomerular mesangial cells also acquire a myofibroblast phenotype and synthesize the same matrix proteins. The origin of interstitial myofibroblasts during fibrosis is a matter of debate, where the cells are proposed to derive from resident fibroblasts, pericytes, perivascular adventitial, epithelial, and/or endothelial sources. Regardless of the origin of the cells, transforming growth factor-beta1 (TGF-β1) is the principal growth factor responsible for myofibroblast differentiation to a profibrotic phenotype and exerts its effects via Smad signaling pathways involving mitogen-activated protein kinase and Akt/protein kinase B. Additionally, reactive oxygen species (ROS) have important roles in progression of fibrosis. ROS are derived from a variety of enzyme sources, of which the nicotinamide adenine dinucleotide phosphate (NAD(P)H) oxidase family has been identified as a major source of superoxide and hydrogen peroxide generation in the cardiovasculature and kidney during health and disease. Recent evidence indicates that the NAD(P)H oxidase homolog Nox4 is most accountable for ROS-induced fibroblast and mesangial cell activation, where it has an essential role in TGF-β1 signaling of fibroblast activation and differentiation into a profibrotic myofibroblast phenotype and matrix production. Information on the role of ROS in mesangial cell and fibroblast signaling is incomplete, and further research on myofibroblast differentiation during fibrosis is warranted.
The Memory and Aging Project is a longitudinal, epidemiologic clinical-pathologic cohort study of common chronic conditions of aging with an emphasis on decline in cognitive and motor function and ...risk of Alzheimer's disease (AD). In this manuscript, we first summarize the study design and methods. Then, we present data on: (1) the relation of motor function to cognition, disability, and death; (2) the relation of risk factors to cognitive and motor outcomes, disability and death; (3) the relation of neuropathologic indices to cognitive outcomes; (4) the relation of risk factors to neuropathologic indices; and (5) additional study findings. The findings are discussed and contextualized.
Plasmonic Materials Murray, W. A.; Barnes, W. L.
Advanced materials (Weinheim),
11/2007, Letnik:
19, Številka:
22
Journal Article
Recenzirano
We provide an overview of the way in which different approaches to nanostructuring metals can lead to a wealth of interesting optical properties and functionality through manipulation of the plasmon ...modes that such structures support, a field known as plasmonics. The increasing interest in plasmonics derives in large measure from the interplay between better fabrication techniques and an awareness of the potential that controlled plasmon modes have to offer. The combination of nanometer‐scale fabrication techniques and increasingly sophisticated numerical modeling capabilities thus enables a significant advance in our understanding of the science underlying plasmonics. Here, we survey some of the different structures that have been explored. We hope that this Review will spur others to continue the exploration of this fascinating topic.
The increasing interest in plasmonics derives in large measure from the interplay between better fabrication techniques and an awareness of the potential that controlled plasmon modes have to offer. The combination of nanometer‐scale fabrication techniques and increasingly sophisticated numerical modeling capabilities thus enables a significant advance in our understanding of the science underlying plasmonics. In this Review, some of the different structures that have been explored are surveyed.
As the US elderly population continues to expand rapidly, Alzheimer's disease poses a major and increasing public health challenge, and older African Americans may be disproportionately burdened by ...the disease. Although African Americans were generally underincluded in previous research studies, new and growing evidence suggests that they may be at increased risk of the disease and that they differ from the non-Hispanic white population in risk factors and disease manifestation. This article offers an overview of the challenges of Alzheimer's disease in African Americans, including diagnosis issues, disparities in risk factors and clinical presentation of disease, and community-based recommendations to enhance research with this population.
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