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Electrically detected magnetic resonance

We compare the results of electrically detected magnetic resonance in a 2D electron gas in Si/SiGe quantum wells with transport and magnetic resonance measurements on ferromagnetic Ga1-xMnxAs. The results lead us to the conclusion that observation of electrically detected magnetic resonance is possible only in the case of a slow spin relaxation, where the microwave resonant absorption leads to a n

Flow cytometric DNA content in Kaposi's sarcoma by histologic stage. Comparison with angiosarcoma

Kaposi's sarcoma occurs as a multicentric proliferation of endothelial cells. A lesion may progress through several histologic stages, culminating in a lesion consisting of spindle cells with marked nuclear atypia that may be indistinguishable from angiosarcoma. To assess the relationship between the nuclear DNA content and the stage, 29 paraffin-embedded biopsy specimens from 25 cases of Kaposi's

Antigenicity of cystatin-binding proteins from parasitic protozoan. Detection by a proteinase inhibitor based capture immunoassay (PINC-ELISA)

A novel immunoassay (PINC-ELISA) was designed using proteinase inhibitors of the cystatin superfamily (PINC) in the solid phase, to promote the selective capture of cysteine proteinases. The method was applied in the identification of papain-like antigens from parasitic protozoa. PINC of human origin, namely recombinant cystatin C (r-cystatin C) or low molecular weight kininogen were used in the a

Genetic diversity of cutaneous human papillomaviruses

Human papillomaviruses (HPVs) of the genera Betapapillomavirus and Gammapapillomavirus are common on human skin. Sequencing of subgenomic amplicons of cutaneous HPVs has revealed a large number of novel putative HPV types within these genera. Phylogenetic analysis based on these amplicons revealed 133 putative HPV types with

AP threshold elevation in the guinea pig following exposure to a broadband noise

Sixty guinea pigs were exposed to a steady-state broadband noise with a falling frequency spectrum. The sound-pressure level was varied between 96 and 117 dB SPL, and the duration of the exposure was varied from 3 to 12 h. After 4-5 weeks, the auditory thresholds were determined by electrocochleography at 14 frequencies, and the results were compared with a control group. With increasing sound-pre

Comparative analyses of population structure in two subspecies of Nigella degenii: Evidence for diversifying selection on pollen-color dimorphisms

Flower color can be a major determinant of plant fitness, not only because of preferential visitation by pollinators but also because of pleiotropic relationships between the expression of floral pigments and biochemically related compounds that influence vegetative performance variables. Different environments may therefore favor different pigmentation phenotypes. We examined whether spatially va

Reactivity of iso-diiodomethane and iso-iodoform, isomers of CH2I2 and CHI3, toward the double bond of a variety of cycloalkenes

The metastable CH2I-I and CHI2-I isomers formed by UV photolysis of CH2I2, and CHI3 transfer methylene and iodomethylene groups, respectively, to a variety of cycloalkenes, leading to their cyclopropanation. More than a 100-fold increase of the reaction rate with increasing solvent polarity suggests a dipolar transition state. The fastest second-order rates observed were in CH3CN. However, CH2Cl2

Determination of the glycaemic index of foods: interlaboratory study.

Objective: Practical use of the glycaemic index (GI), as recommended by the FAO/WHO, requires an evaluation of the recommended method. Our purpose was to determine the magnitude and sources of variation of the GI values obtained by experienced investigators in different international centres. Design: GI values of four centrally provided foods (instant potato, rice, spaghetti and barley) and local

Protein microchip bioassay with dual fluorescent- and MALDI read-out.

Protein Microchip Array technology makes it possible to examine patterns of protein expressions and modifications. Current technologies such as two-dimensional get electrophoresis (2-DE) in combination with mass spectrometry allows the identification of biologically relevant proteins with high resolving power, but has also considerable limitations. Most spots observed in 2-DE are from high abundan

Current-voltage correlations in interferometers

We investigate correlations of current at contacts and voltage fluctuations at voltage probes coupled to interferometers. The results are compared with correlations of current and occupation number fluctuations at dephasing probes. We use a quantum Langevin approach for the average quantities and their fluctuations. For higher order correlations we develop a stochastic path integral approach and f

Friends and foes in foraging: intraspecific interactions act on foraging-cycle stages

Intraspecific interactions may increase or decrease foraging rates of individual consumers, and such facilitation or interference interactions should affect individual foraging economies as well as predator-prey processes at the population level. To mechanistically predict individual foraging performance, we need to investigate the effects of positive and negative interactions on separate foraging

A functional analysis of compound eye evolution.

New data on the phylogenetic relationships of various arthropod groups have spurred interesting attempts to reconstruct the evolution of arthropod nervous and visual systems. Some of the relevant new data are cell identities and developmental processes in the nervous and sensory systems, which is particularly useful for reconstructing the evolution of these systems. Here, we focus on the structure