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One-dimensional arrays of nanoshell dimers for single molecule spectroscopy via surface-enhanced raman scattering

The optical properties of one-dimensional arrays of metal nanoshell dimers are studied systematically using the T-matrix method based on Mie theory, within the context of surface enhanced Raman scattering (SERS). It is shown that the local electromagnetic enhancement can be as high as similar to 4.5x10(13) for nanoshell dimer arrays with optimal geometry, and sensitive tunability in the resonant f

The structure and dynamic behaviour of disubstituted derivatives of Rh6(CO)16 containing heterobidentate bridging phosphine ligands

The solution structures and dynamic behaviour of [Rh6(CO)14(µ-PX)][PX = diphenyl(2-pyridyl)phosphine, (PN); diphenyl(2-thienyl)phosphine, (PS); diphenyl(vinyl)phosphine, (PV)] have been studied by multinuclear NMR and the X-ray structure of [Rh6(CO)14(µ,3-PV)] is reported. In solution, the above clusters undergo a variety of localised CO-exchanges and the mechanisms of these are discussed. The PV

Electronic structure of carbon nanostripes

Carbon nanostripes of graphene structure prepared on the stepped Ni(771) surface have been studied by angle-resolved photoemission. The electronic structure is anisotropic: parallel to the stripe direction, a graphite-type dispersion is measured, whereas the perpendicular direction displays two entangled band structures shifted in energy with respect to each other. These are experimentally identif

Initial stability of ankle arthrodesis with three-screw fixation. A finite element analysis

Objective. Compare the initial stability at the fusion site of ankle arthrodesis fixed with two and three screws. Design. Finite element models of ankle arthrodesis were developed from computed tomography images. Two-screw constructs were augmented with a third screw in different orientations and Subjected to loads likely to affect the ankle postoperatively. Background More stable fixation seems t

Are fish populations in temperate streams affected by crayfish? - A field survey and prospects

Fish populations may be affected by predation and competition from various types of organisms, among which crayfish have been suggested as important actors. We here present results from stream surveys, suggesting that neither native noble, Astacus astacus, nor introduced signal crayfish, Pacifastacus leniusculus, necessarily affect fish population densities in temperate stream communities. Compari

Habitat selection and population regulation in temporally fluctuating environments

Understanding and predicting the distribution of organisms in heterogeneous environments lies at the heart of ecology, and the theory of density-dependent habitat selection (DDHS) provides ecologists with an inferential framework linking evolution and population dynamics. Current theory does not allow for temporal variation in habitat quality, a serious limitation when confronted with real ecologi

Analysis and understanding of high-dimensionality data by means of multivariate data analysis

Multivariate analysis such as principal-components analysis (PCA) and partial-least-squares-discriminant analysis (PLS-DA) have been applied to peptidomics data from clinical urine samples subjected to LC/MS analysis. We show that it is possible to use these methods to get information from a complex set of clinical data. The aim of the work is to use this information as a first step in the further

Treatment of skin papillomas with topical alpha-lactalbumin-oleic acid

BACKGROUND: We studied the effect on skin papillomas of topical application of a complex of α-lactalbumin and oleic acid (often referred to as human α-lactalbumin made lethal to tumor cells [HAMLET]) to establish proof of the principle that α-lactalbumin-oleic acid kills transformed cells but not healthy, differentiated cells. METHODS: Forty patients with cutaneous papillomas that were resistant t

0(gs)+ -->2(1)+ transition strengths in 106Sn and 108Sn.

The reduced transition probabilities, B(E2; 0(gs)+ -->2(1)+), have been measured in the radioactive isotopes (108,106)Sn using subbarrier Coulomb excitation at the REX-ISOLDE facility at CERN. Deexcitation gamma rays were detected by the highly segmented MINIBALL Ge-detector array. The results, B(E2;0(gs)+ -->2(1)+)=0.222(19)e2b2 for 108Sn and B(E2; 0(gs)+-->2(1)+)=0.195(39)e2b2 for 106Sn were det

Identification of an amino acid residue in the PKC C1b domain crucial for its localisation to the Golgi network.

Protein kinase C (PKC) isoforms have been reported to be targeted to the Golgi complex via their C1 domains. We have shown recently that the regulatory domain of PKCtheta induces apoptosis in neuroblastoma cells and that this effect is correlated to Golgi localization via the C1b domain. This study was designed to identify specific residues in the C1 domains that mediate Golgi localization. We dem

ID2 expression in neuroblastoma does not correlate to MYCN levels and lacks prognostic value

The MYCN proto-oncogene is frequently amplified in a subgroup of highly aggressive neuroblastomas. The molecular mechanism(s) by which the overexpressed MYCN contributes to an aggressive tumor cell behavior is not well understood. Recently, it was reported that the ID2 gene is a direct target for the MYCN and MYC transcription factors, and that ID2 expression and MYCN amplification correlate posit

Retreat from Salix - Swedish experience with energy crops in the 1990s

A wave of Salix (willow) planting rolled over Sweden in the early 1990s, driven by subsidies and optimistic market expectations. The expected economic life span of such investments is 20 years or more. But in fact, many plantations were terminated or reduced much sooner. This article explores the reasons for this retreat. In a survey to Salix farmers, 41 per cent either have retreated or regretted

Structural development of self nano emulsifying drug delivery systems (SNEDDS) during In vitro lipid digestion monitored by small-angle x-ray scattering

Purpose. To investigate the structural development of the colloid phases generated during lipolysis of a lipid-based formulation in an in vitro lipolysis model, which simulates digestion in the small intestine. Materials and Methods. Small-Angle X-Ray scattering (SAXS) coupled with the in vitro lipolysis model which accurately reproduces the solubilizing environment in the gastrointestinal tract a

Process-based modelling of biogenic monoterpene emissions combining production and release from storage

Monoterpenes, primarily emitted by terrestrial vegetation, can influence atmospheric ozone chemistry, and can form precursors for secondary organic aerosol. The short-term emissions of monoterpenes have been well studied and understood, but their long-term variability, which is particularly important for atmospheric chemistry, has not. This understanding is crucial for the understanding of future

Visualization of chromatic correction of fish lenses by multiple focal lengths

Many fish and some terrestrial animals have multifocal lenses that compensate for chromatic aberration by a mechanism unique to biological optical systems. We describe four optical methods for the study of such lenses. Significantly improved methods (focal-area imaging, schlieren photography, and laser scanning) are explained in full detail. One method (photorefractometry) was only slightly modifi

Everyday ethics in the care of elderly people

This article analyses the general ethical milieu in a nursing home for elderly residents and provides a decision-making model for analysing the ethical situations that arise. It considers what it means for the residents to live together and for the staff to be in ethically problematic situations when caring for residents. An interpretative phenomenological approach and Sandman’s ethical model prov

Infanticide in great reed warblers: secondary females destroy eggs of primary females

In 1993-1995 artificial nests with attached model eggs were put into territories that were known to have been occupied by male great reed warblers, Acrocephalus arundinaceus, in previous years. Because the eggs were made of soft plasticine, predators left peckmarks in them and this enabled us to identify predators by comparing peckmarks with reference marks made by Various species. Previous field