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Et Al. Report (et + al._report)

Distribution by Scientific Domains
Polymers and Materials Science69%
Life Sciences23%

Selected Abstracts

Nanostructures: Biodegradable Porous Silicon Barcode Nanowires with Defined Geometry (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 14 2010
Mater.
The cover illustrates a forest of bicolor porous silicon nanowires with modulated porosity. M. Ferrari et al. report on page 2231 the synthesis of biodegradable porous silicon barcode nanowires with segment-specific morphological, mechanical, and photonic properties by metal-assisted etching. The presented phase diagrams of nanostructures contribute to clarify the competing roles of metal nanoparticles and ions in the formation of various silicon nanostructures, enabling application-specific design. [source]

Shape Memory Materials: Identification of Quaternary Shape Memory Alloys with Near-Zero Thermal Hysteresis and Unprecedented Functional Stability (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 12 2010
Mater.
On page 1917, R. Zarnetta et al. report that for the reversible martensitic transformation in shape memory alloys the compatibility at the austenite/martensite interface is directly related to the width of the thermal hysteresis and to the functional stability. A "perfect" compatibility results in the growth of twinless martensite (blue) within the austenite (red), as shown in the TEM image for a Ti50Ni39Pd11 shape memory alloy (image provided courtesy of R. Delville). [source]

Metamaterials: How Far Are We from Making Metamaterials by Self-Organization?

ADVANCED FUNCTIONAL MATERIALS, Issue 7 2010
The Microstructure of Highly Anisotropic Particles with an SRR-Like Geometry (Adv. Funct.
As part of ongoing efforts to create metamaterials by engineered self-organization using solidification of eutectics, D. A. Pawlak et al. report on page 1116 the fabrication of a fractal material with split-tubes mimicking (in cross section) the famous split-ring resonators (SRRs). The latter, when made of metal, are the basic element of a structure showing negative refractive index. This article shows that metallo-dielectric structures can be fabricated. The method employed has high potential for manufacturing materials with various functionalities. [source]

Nanolithography: Thermochemical Nanolithography of Multifunctional Nanotemplates for Assembling Nano-Objects (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 23 2009
Mater.
On page 3696, Wang et al. report on the nanoscale chemical surface patterning of different chemical species (amine, thiol, aldehyde, and biotin) in independent nanopatterns by the iterative application of thermochemical nanolithography. Due to the unique chemical stability of the patterns, the resultant substrates can be stored for weeks and subsequently be used for the selective attachment of nanometer-sized objects, such as proteins or DNA, using standard chemical protocols. [source]

Morphology-Tunable Micro/Nanostructures: Characterization, Cathodoluminescence, and Field-Emission Properties of Morphology-Tunable CdS Micro/Nanostructures (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 15 2009
Mater.
On page 2423, T. Y. Zhai et al. report that high quality and uniform 1D CdS micro/nanostructures with different morphologies can be fabricated through a simple and effective thermal evaporation process. Both cathodoluminescence and field-emission measurements are made and clear correlations between morphology, structure, and optical and field emission performance are established. [source]

Nanostructure Fracturing: Brittle-to-Ductile Transition in Uniaxial Compression of Silicon Pillars at Room Temperature (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 15 2009
Mater.
On page 2439, F. Östlund et al. report on an interesting effect observed during the compression of sub-micrometer silicon pillars; a critical diameter separates pillars that are observed to crack from pillars that exhibit metal-like ductility. This observation allows for the development of a quantitative method for measuring the fracture toughness of such structures, which can be used to predict and explain small-volume fracture behavior. [source]

Photovoltaic Cells: Organic Photovoltaic Cells Based On Solvent-Annealed, Textured Titanyl Phthalocyanine/C60 Heterojunctions (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 12 2009
Mater.
D. Placencia et al. report on the creation of organic photovoltaic cells from textured titanyl phthalocyanine (TiOPc) heterojunctions. The foreground of this frontispiece shows the crystal structures of the two polymorphs of TiOPc used, along with FE-SEM images of TiOPc on an ITO electrode before (left), and after (right) phase transformation of the TiOPc film. The background shows AFM phase images of the two TiOPc polymorph films, showing the dewetting of the surface and the nanotexturing which occurs during the solvent annealing/phase transformation process. [source]

Nanocrystal Shape Control: Synthesis and Structure,Property Correlation in Shape-Controlled ZnO Nanoparticles Prepared by Chemical Vapor Synthesis and their Application in Dye-Sensitized Solar Cells (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 6 2009
Mater.
Chemical vapor synthesis is a convenient one-step synthesis process for the production of nanocrystalline powders. On page 875, Bacsa et al. report that by controlled variation of experimental parameters, tetrapods (as in image) or spherical ZnO nanocrystals can be selectively obtained directly from Zn metal precursor. Shape control leads to improved optical properties and a better performance when applied as electrodes in dye sensitized solar cells. [source]

Organic Electronics: Improved Performance of Polymer Bulk Heterojunction Solar Cells Through the Reduction of Phase Separation via Solvent Additives (Adv. Mater.

ADVANCED MATERIALS, Issue 8 2010
8/2010)
The fabrication of bulk heterojunction organic solar cells from solution-casting techniques using low-cost materials makes them a promising new technology for converting sunlight into electricity. T.-Q. Nguyen, G. C. Bazan, et al. report on p. E63 that undesirable large-scale aggregation and phase separation that may arise during deposition can be reduced by incorporating a small amount of a well-chosen solvent additive. [source]

Evolution rampant: house mice on Madeira

MOLECULAR ECOLOGY, Issue 21 2009
R. J. BERRY
House mice are extra-ordinary animals ,extra -ordinary in the literal sense of that word. They are pests , but also a valued laboratory animal. They are generalized rodents , and successful in habitats from tundra to tropics and from sea-level to high altitudes. They have differentiated into a perplexity of taxa, yet differ little in their general morphology. They were long scorned by ecologists as recently arrived commensals, but are increasingly illuminating evolutionary processes as new techniques are applied to their study. Local forms, once valued only by taxonomists, are proving ever more interesting as their genetics are probed. In 1992, Mathias & Mira described the apparently unexciting characteristics of mice living on the two main islands of the Madeira group, 600 km west of continental Portugal. Then in 2000, Britton-Davidian et al. discovered that there were at least six chromosomal (Robertsonian) races on the main island. In the past decade, studies of molecular and mitochondrial genomes have shown an array of variables and posed questions about the origins and subsequent evolution of these island mice. In this issue of Molecular Ecology, Förster et al. report on the mtDNA haplotypes found on the island and in mainland Portugal, discuss the probable source of the island colonizers, and consider data which might give information about the timing of the colonizing event(s). [source]

MicroRNA mutant turns back the evolutionary clock for fly olfaction

BIOESSAYS, Issue 7 2008
Walton D. Jones
In a recent paper, Cayirlioglu et al. report that the disruption of a specific miRNA, miR-279, which normally acts to inhibit the transcription factor Nerfin-1, uncovers a population of hybrid CO2 neurons in the Drosophila maxillary palp.1 Normally, fruit fly CO2 neurons are found only in the antennae, while mosquito CO2 neurons are found only in the maxillary palps. The hybrid neurons in this miRNA mutant may, thus, recapitulate an evolutionary intermediate unseen since the divergence of these two dipteran lineages over 250 million years ago. BioEssays 30:621,623, 2008. © 2008 Wiley Periodicals, Inc. [source]

Genetic caste determination in termites: out of the shade but not from Mars

BIOESSAYS, Issue 4 2008
Ross H Crozier
Several ant species are known with genetic effects on caste determination but, for termites, the role of environment has been assumed to be omnipotent. Now Hayashi et al. report that commitment to the nymph and worker pathways in Reticulitermes speratus follows a simple model involving two alleles at a sex-linked locus.1 The spread of this system of genetic caste determination seems best explained by selection at the colony level. This remarkable system may be widely applicable throughout termites, although it cannot be universal, and may provide a window into causal aspects of the molecular biology of caste determination. BioEssays 30:299,302, 2008. © 2008 Wiley Periodicals, Inc. [source]

Feeding practices of HIV-1-infected mothers: The role of counsellors

ACTA PAEDIATRICA, Issue 3 2005
Anneka EHRNST
Abstract In this issue of Acta Paediatrica, Chopra et al. report that voluntary counselling is central to preparing mothers for making a proper informed choice about adequate feeding practices to prevent their infants from acquiring HIV infection. The recommendations given and the way in which counselling is performed are the most important determinants of a mother's decision about how to feed her infant. In this article, we summarize the main arguments for and against breastfeeding by HIV-infected mothers. Conclusions : Further studies are needed to determine the alternatives to breastfeeding in countries where there is no access to safe formula feeding or to antiretroviral drugs. HIV-positive mothers should be made aware of the available feeding alternatives through adequate counselling from properly trained persons. [source]