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A new route to produce efficient surface-enhanced Raman spectroscopy substrates : Gold-decorated CdSe nanowires

Surface-enhanced Raman spectroscopy is a popular tool for the detection of extremely small quantities of target molecules. Au nanoparticles have been very successful in this respect due to local enhancement of the light intensity caused by their plasmon resonance. Furthermore, Au nanoparticles are biocompatible, and target substances can be easily attached to their surface. Here, we demonstrate th

Chemically induced self-assembly of spherical and anisotropic inorganic nanocrystals

The self-assembly of inorganic nanoparticles is a research area of great interest aiming at the fabrication of unique mesostructured materials with intrinsic properties. Although many assembly strategies have been reported over the years, chemically induced self-assembly remains one of the dominant approaches to achieve a high level of nanoparticle organization. In this feature article we will rev

Synthesis and characterization of azidoalkyl-functionalized gold nanoparticles as scaffolds for "click"-chemistry derivatization

We demonstrate how water-soluble gold nanoparticles prepared by the citrate reduction method can be functionalized with 11-azidoundecane-1-thiol in a single-step procedure, which combines phase transfer and ligand exchange. The advantages of our method include high reproducibility, low cost of gold nanoparticle production, and rapid and clean ligand exchange, with minimal intermediate steps and no

Assembly of shape-controlled nanocrystals by depletion attraction

Recently (Baranov et al., Nano Lett., 2010, 10, 743) we demonstrated that depletion attraction between semiconductor nanorods in solution can be employed for both their self-assembly and their separation from spherical nanoparticles. Here we show that depletion attraction can be used to fabricate binary superlattices of nanorods and 3D networks of octapod/tetrapod-shaped nanocrystals.

Phototransport in networks of tetrapod-shaped colloidal semiconductor nanocrystals

Tetrapod-shaped CdSe(core)/CdTe(arms) colloidal nanocrystals, capped with alkylphosphonic acids or pyridine, were reacted with various small molecules (acetic acid, hydrazine and chlorosilane) which induced their tip-to-tip assembly into soluble networks. These networks were subsequently processed into films by drop casting and their photoconductive properties were studied. We observed that films

Assembly of colloidal semiconductor nanorods in solution by depletion attraction

Arranging anisotropic nanoparticles into ordered assemblies remains a challenging quest requiring innovative and Ingenuous approaches. The variety of interactions present in colloidal solutions of nonspherical inorganic nanocrystals can be exploited for this purpose. By tuning depletion attraction forces between hydrophobic colloidal nanorods of semiconductors, dispersed in an organic solvent, the

Synthesis of cobalt-containing nanoparticles by cobalt formate thermolysis in hydrocarbon oil without stabilizing ligands

A simple and available method is proposed for the synthesis of cobalt-containing nanoparticles. This method comprises cobalt formate thermolysis in hydrocarbon oil without extra stabilizing ligands. The size, composition, and structure of the nanoparticles are determined by transmission electron microscopy, X-ray powder diffraction, and electron diffraction. The average particle size is 10-14 nm.

Synthesis of flexible, ultrathin gold nanowires in organic media

Gold nanoparticles are very interesting because of their potential applications in microelectronics, optical devices, analytical detection schemes, and biomedicine. Though shape control has been achieved in several polar solvents, the capability to prepare organosols containing elongated gold nanoparticles has been very limited. In this work we report a novel, simplified method to produce long, th

Organization of magnetic/noble metal heterostructures by an applied external magnetic field

This paper describes the synthesis of binary nanoparticles consisting of a noble metal and a magnetic component. These heterostructures were produced by a seeded-growth approach in aqueous solution. FePt nanoparticles, as the magnetic component, were first synthesized in an organic medium, subsequently transferred into water, and finally used as seeds for the growth of the noble metal Au. This pro

Länsstyrelsen och o-djuret. : Lek som strategi i fridlysningen av Storsjöodjuret 1985-2005

In 1985 the County Administrative Board of Jämtland initiated a process to protect Storsjöodjuret (the Great Lake Monster). As other famous cryptids, the Monster has become a valuable resource in the process of cultural heritage, marketing and tourism. We apply Bateson’s theories of play (1972) and Goffman’s concept of frame (1974) to show how play offers a metacommunicative strategy to circumvent

Utgrävningarna av gravfältet i Vätteryd

Mellan åren 1955 och 1957 utförde Märta Strömberg (sedermera professor i arkeologi) och Rolf Petré (som senare blev fil. lic. i arkeologi) arkeologiska undersökningar av Vätterydsgravfältet i norra Mellby socken (L1990:1893 / Norra Mellby 1:1) ...

NEW PARTITION IDENTITIES FROM C(1) -MODULES

In this paper we conjecture combinatorial Rogers-Ramanujan type colored partition identities related to standard representations of the affine Lie algebra of type C(1) ℓ, ℓ ≥ 2, and we conjecture similar colored partition identities with no obvious connection to representation theory of affine Lie algebras.

Roles of unconventional ion channels and insulin granule structure in the pathogenesis of type-2 diabetes

T2D is the most widespread endocrine disease. In conventional stimulus secretion coupling increased blood glucose is metabolized causing an increased intracellular level of ATP and closure of the KATP channels, and this, in turn, depolarizes the cell membrane leading to the opening of voltage-gated Ca2+ channels, the influx of Ca2+ and exocytosis of insulin granules. This model has become almost a

An Economic Model for Estimating Trial Costs with an Application to Placebo Surgery Trials

Background and Objective: Waste in clinical trials remains rife. We developed an economic model to predict the cost of trials based on input costs, duration, power, number of sites, recruitment eligibility and consenting rates. Methods: We parameterised the model for three proxy placebo-controlled surgical trials using data from a systematic review, a bespoke cost survey, and from the literature.

Praktiska case för politikens genomslag

Att träna samspel mellan politik och förvaltning kan vara en god idé efter val. Ett sätt att göra detta är att diskutera case tillsammans. Med utgångspunkt i forskning om styrning av offentlig sektor och case pedagogikens fördelar diskuterar författarna vad som kan underlätta eller försvåra förverkligandet av politiska beslutPracticing interaction between politics and administration can be a good idea after elections. One way to do this is to discuss cases together. Based on research on governance and control of the public sector and the advantages of case pedagogy, the authors discuss what can facilitate or hinder the realization of political decisions

Genomic studies of sex differences : On mutations, recombination, and sexual antagonism in songbirds

Many organisms have separate sexes, i.e., males and females. The presence of separate sexes causes sex-specific selection regimes and sexual antagonism, which can lead to sex differences in morphology, physiology, and behaviours. Sex and sex differences can be genetically governed and regulated by a pair of sex chromosomes (e.g., X and Y, or Z and W), on which there often are regions without recom

Health-related quality of life as associated with asthma control, psychological status and insomnia

Background: Asthma is associated not only with lower health-related quality of life (HRQL) but also with psychological health and insomnia. The aim of this study was to investigate associations between HRQL, asthma symptoms, psychological status and insomnia in adults from three Nordic countries. Methods: This study comprised 2,270 subjects aged 29-55 from Sweden, Iceland and Norway. HRQL was meas