tion of individual protein molecules or complexes than an extended, homogeneous surface. Of course, this hypothesis needs to be tested by biological activity. ExperimentalSize-selected metal (Au) clusters, with size between 1 and 100 atoms, were generated by an RF (radio-frequency) magnetron sputtering, gas condensation [20,21] cluster beam source and mass selected to within 5 % by a novel, lateral time-of-flight mass filter to control the cluster size, as described previously [22]. The energetic beam of ionized Au clusters was deposited on a graphite substrate with sufficient kinetic energy to ªpinº the clusters to their individual points of impact on the surface. The underlying mechanism of pinning is the displacement of a surface carbon atom to create a reactive binding site which prevents the characteristic diffusion and aggregation of clusters observed at lower incident energies [15,16]. In this work we found that such monodispersed cluster films were stable not only at room temperature but also at temperatures up to 200 C. They are also stable when placed in an autoclave (130 C for 2 h in high pressure steam) to sterilize the surface. The Au 17 + clusters were produced with an Ar flow of 60 sccm and a He flow of 25 sccm (total gas pressure of 0.4 mbar). Typical sputtering parameters were: RF power 25 W; self-bias voltage of the target 372 V. The cluster samples were imaged in ambient conditions with a bench-top STM (DME Rasterscope 4000). Typical imaging parameters were 0.4 V and 0.4 nA (using mechanically cut Pt/Ir tips). All AFM measurements were collected from a Digital Instruments DI3100 equipped with a Nanoscope IIIa controller and a liquid cell holder. Commercial oxide sharpened silicon nitride tips with nominal spring constant of either 0.38 or 0.60 N m ±1 were used for imaging.

The creation of a new material often starts from the design of its constituent building blocks at a smaller scale. From macromolecules to colloidal architectures, to granular systems, the interactions between basic units of matter can dictate the macroscopic behaviour of the resulting engineered material and even regulate its genesis. Information can be imparted to the building units by altering their physical and chemical properties. In particular, the shape of building blocks has a fundamental role at the colloidal scale, as it can govern the self-organization of particles into hierarchical structures and ultimately into the desired material. Herein we report a simple and general approach to generate an entire zoo of new anisotropic colloids. Our method is based on a controlled deformation of multiphase colloidal particles that can be selectively liquified, polymerized, dissolved and functionalized in bulk. We further demonstrate control over the particle functionalization and coating by realizing patchy and Janus colloids.

The self-assembly of triblock copolymers of poly(ethylene oxide-b-methyl methacrylate-b-styrene) (PEO-b-PMMA-b-PS), where PS is the major component and PMMA and PEO are minor components, provides a robust route to highly ordered, nanoporous arrays with cylindrical pores of 10-15 nm that show promise in block copolymer lithography. These ABC triblock copolymers were synthesized by controlled living radical polymerization, and after solvent annealing, thin films showing defect-free cylindrical microdomains were obtained. The key to the successful generation of highly regular, porous thin films is the use of PMMA as a photodegradable mid-block which leads to nanoporous structures with an unprecedented degree of lateral order. The power of using a triblock copolymer when compared to a traditional diblock copolymer is evidenced by the ability to exploit and combine the advantages of two separate diblock copolymer systems, the high degree of lateral ordering inherent in PS-b-PEO diblocks plus the facile degradability of PS-b-PMMA diblock copolymer systems, while negating the corresponding disadvantages, poor degradability in PS-b-PEO systems and no long-range order for PS-b-PMMA diblocks.

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Breakthroughs in molecular medicine have positioned the amyloid-β (Aβ) pathway at the center of Alzheimer’s disease (AD) pathophysiology. While the detailed molecular mechanisms of the pathway and the spatial-temporal dynamics leading to synaptic failure, neurodegeneration, and clinical onset are still under intense investigation, the established biochemical alterations of the Aβ cycle remain the core biological hallmark of AD and are promising targets for the development of disease-modifying therapies. Here, we systematically review and update the vast state-of-the-art literature of Aβ science with evidence from basic research studies to human genetic and multi-modal biomarker investigations, which supports a crucial role of Aβ pathway dyshomeostasis in AD pathophysiological dynamics. We discuss the evidence highlighting a differentiated interaction of distinct Aβ species with other AD-related biological mechanisms, such as tau-mediated, neuroimmune and inflammatory changes, as well as a neurochemical imbalance. Through the lens of the latest development of multimodal in vivo biomarkers of AD, this cross-disciplinary review examines the compelling hypothesis- and data-driven rationale for Aβ-targeting therapeutic strategies in development for the early treatment of AD.

Lipopolysaccharide (LPS) increases the production of interleukin-12 (IL-12

The self-assembly of materials is emerging as a key process in the fabrication of functional nanostructured materials, since it provides a powerful ªbottom±upº route to well-organized structures on the nanometer scale. The last few years have seen considerable progress in the development of concepts and methods for generating a variety of nano-and microstructured materials by using such a strategy.[1] Block copolymers, one class of self-assembling materials, offer an attractive route to fabricating nanometer-scale structures, since they spontaneously form a range of well-defined, well-ordered structures including spheres, cylinders, and lamellae, depending on the volume fractions of the components. In addition, the molecular weight of the copolymer provides control over the size and separation distances of the microdomains, and the specific functionality can be incorporated into the structure by varying the chemical nature of the copolymer. This versatility makes block copolymers ideal candidates for use as templates and scaffolds for applications ranging from magnetic storage to displays and sensors. Tremendous progress and innumerable examples have been reported in the last decade.[2±15] Control of well-organized structures over large scales is still challenging and, in most cases of the use of block copolymers, the lack of long-range order can limit their utilization. For applications requiring addressability, long-range lateral order and orientation of elements are key, and therefore self-assembly is no longer sufficient. Rather, a directed self-assembly or a biased, directed self-assembly is required wherein the precise location of each nanoscopic element is defined by external forces, such as electric fields, [10,16] shear forces, [17,18] temperature gradients, [19] graphoepitaxy, [9,20,21] crystallization, [22,23] chemically patterned substrates, [24±27] or controlled interfacial interactions. [28,29] Very recently, we showed that solvent evaporation at a controlled rate can provide a very simple but robust route to generating almost defect-free microstructures over large areas in block-copolymer films. [30,31] Solvent evaporation is a strong, highly directional field. Strong repulsion between the copolymer blocks, combined with the directionality of solvent evaporation, where ordering is initiated at the surface of the film and propagates through the entire film, leads to a high degree of long-range lateral order with few defects.[31±34]Moreover, the use of a cosolvent enables one to control the characteristic length scales in the block-copolymer structures even further. Here, the same strategy is applied to a mixture of a block copolymer with a small amount of homopolymer, which provides another way to control the characteristic dimensions of the morphologies. The addition of homopolymers makes the phase diagram of the system more complicated due to the coexistence of micro-and macrophase separation.[35±41] However, at low homopolymer concentrations, or when the homopolymer molecular weight is below o...

PurposeThe aim of this study is to report on preliminary data regarding the prevalence of major eye diseases in Korea.MethodsWe obtained data from the Korea National Health and Nutrition Examination Survey, a nation-wide cross-sectional survey and examinations of the non-institutionalized civilian population in South Korea (n = 14,606), conducted from July 2008 to December 2009. Field survey teams included an ophthalmologist, nurses, and interviewers, traveled with a mobile examination unit and performed interviews and ophthalmologic examinations.ResultsThe prevalence of visual impairment, myopia, hyperopia and astigmatism in participants over 5 years of age was 0.4 ± 0.1%, 53.7 ± 0.6%, 10.7 ± 0.4%, and 58.0 ± 0.6%, respectively. The prevalence of strabismus and blepharoptosis in participants over 3 years of age was 1.5 ± 0.1% and 11.0 ± 0.8%, respectively. In participants over 40 years of age, the prevalence of cataract, pterygium, early and late age-related macular degeneration, diabetic retinopathy and glaucoma was 40.2 ± 1.3%, 8.9 ± 0.5%, 5.1 ± 0.3%, 0.5 ± 0.1%, 13.4 ± 1.5%, and 2.1 ± 0.2%, respectively.ConclusionsThis is the first nation-wide epidemiologic study conducted in South Korea for assessment of the prevalence of eye diseases by both the Korean Ophthalmologic Society and the Korea Center for Disease Control and Prevention. This study will provide preliminary information for use in further investigation, prevention, and management of eye diseases in Korea.