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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

Refined myoelectric control in below-elbow amputees using artificial neural networks and data glove

Purpose: To develop a system for refined motor control of artificial hands based on multiple electromyographic (EMG) recordings, allowing multiple patterns of hand movements. Methods: Five subjects with traumatic below-elbow amputations and 1 subject with a congenital below-elbow failure of formation performed 10 imaginary movements with their phantom hand while surface electrodes recorded the EMG

Detection and prevention of hepatitis C in dialysis patients and renal transplant recipients. A long-term follow up (1989-january 1997)

Background. Hepatitis C is frequent problem in dialysis wards. Design. A long time (1989-97) follow up of hepatitis C virus (HCV) infection in a Swedish nephrology unit was performed with anti-HCV screening, confirmatory antibody tests, viral RNA detection and molecular characterization. Case histories were reviewed with focus, onset of infection, liver morbidity and mortality. Results. In October