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Correlation spectroscopy of excitons and biexcitons on a single quantum dot

We report the observation of antibunched emission from single self-assembled InAs quantum dots under various conditions. We have measured the correlation function of the photon emission pertaining to single emission lines from single quantum dots under continuous and pulsed laser excitation, as well as under continuous white light excitation. The measurements were performed under different excitat

Ontologies and construals in lexical semantics

The purpose of this paper is to propose a framework of lexical meaning, broadly along the lines of Cognitive Semantics (Langacker 1987). Within the proposed model, all aspects of meaning are to be explained in terms of properties of ontologies in conceptual space, i.e. properties of content ontologies and schematic ontologies and construals which are imposed on the conceptual structures on the occ

Collagen-binding proteoglycan fibromodulin can determine stroma matrix structure and fluid balance in experimental carcinoma.

Research on the biology of the tumor stroma has the potential to lead to development of more effective treatment regimes enhancing the efficacy of drug-based treatment of solid malignancies. Tumor stroma is characterized by distorted blood vessels and activated connective tissue cells producing a collagen-rich matrix, which is accompanied by elevated interstitial fluid pressure (IFP), indicating a

Sexual risk behaviour in women carriers of Mycoplasma hominis

OBJECTIVE: To study the sexual behaviour of women harbouring Mycoplasma hominis in the vagina. SETTING: Two family planning clinics and a youth clinic for contraceptive advice. METHODS: The vaginal flora of 996 women were investigated microbiologically, including culturing for M. hominis from the posterior vaginal fornix. Cultures and tests were also made to diagnose genital Chlamydia trachomatis

A note on renegotiation in repeated Bertrand duopolies

Weak Renegotiation-Proofness (WW) singles out marginal cost pricing as a unique pure-strategy equilibrium of the infinitely repeated Bertrand duopoly. We show that, with a discrete strategy space, WRP does not eliminate any relevant subgame perfect equilibrium outcome. (c) 2006 Elsevier B.V. All rights reserved.

Evaporation and deposition of alkyl-capped silicon nanocrystals in ultrahigh vacuum

Nanocrystals are under active investigation because of their interesting size- dependent properties(1,2) and potential applications(3-5). Silicon nanocrystals have been studied for possible uses in optoelectronics(6), and may be relevant to the understanding of natural processes such as lightning strikes(7). Gas-phase methods can be used to prepare nanocrystals, and mass spectrometric techniques h

Status of the Integrated Model of the Euro50

The Euro50 is a proposed 50m extremely large telescope for optical and infrared wavelengths. To study and predict the performance of the complete telescope system, an integrated model combining the structural model of the telescope, optics models, the control systems and the adaptive optics has been established. Wind and atmospheric disturbances are also included in the model. The integrated model

Risk factors for extrahepatic biliary tract carcinoma in men: medical conditions and lifestyle: results from a European multicentre case-control study

OBJECTIVES: To identify risk factors of carcinoma of the extrahepatic biliary tract in men. METHODS: Newly diagnosed and histologically confirmed patients, 35-70 years old, were interviewed between 1995 and 1997 in Denmark, Sweden, France, Germany and Italy. Population controls were frequency-matched by age and region. Adjusted odds ratios and 95%-confidence intervals were estimated by logistic re

Degradation of Mannan I and II Crystals by Fungal endo-β-1,4-Mannanases and a β-1,4-Mannosidase Studied with Transmission Electron Microscopy

We have used the endo-β-1,4-mannanase from Trichoderma reesei (Tr Man5A), the endo-β-1,4-mannanase from Aspergillus niger (An Man5A) and the exo-β-1,4-mannosidase from A. niger (An Mnd2A) to follow the enzymatic degradation of mannan I and II crystals. The degradation process was studied by transmission electron microscopy and also followed by analysis of the released soluble reducing sugars. The

Classification of breast cancer using genetic algorithms and tissue microarrays

PURPOSE: A multitude of breast cancer mRNA profiling studies has stratified breast cancer and defined gene sets that correlate with outcome. However, the number of genes used to predict patient outcome or define tumor subtypes by RNA expression studies is variable, nonoverlapping, and generally requires specialized technologies that are beyond those used in the routine pathology laboratory. It wou

Dynamics of parasitemia of malaria parasites in a naturally and experimentally infected migratory songbird, the great reed warbler Acrocephalus arundinaceus

Little is known about the development of infection of malaria parasites of the genus Plasmodium in wild birds. We used qPCR, targeting specific mitochondrial lineages of Plasmodium ashfordi (GRW2) and Plasmodium relictum (GRW4), to monitor changes in intensities of parasitemia in captive great reed warblers Acrocephalus arundinaceus from summer to spring. The study involved both naturally infected

Muscular rest and gap frequency as EMG measures of physical exposure: the impact of work tasks and individual related factors

Owing to an orderly recruitment of motor units, low threshold type I fibres are presumed to be vulnerable in contractions of long duration. To study load on these fibres muscular rest was registered as the time fraction of electromyographic (EMG) activity below a threshold. Moreover, the frequency of periods with muscular rest, EMG gaps, was derived, since a low gap frequency has been shown to be

Healthy skin of many animal species harbors papillomaviruses which are closely related to their human counterparts.

Papillomaviruses associated with clinical symptoms have been found in many vertebrate species. In this study, we have used an L1 gene consensus PCR test designed to detect a broad spectrum of human skin papillomaviruses to analyze swab samples from healthy skin of 111 animals belonging to 19 vertebrate species. In eight of the species, papillomavirus DNA was found with the following prevalences: c