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Refractometry of microscopic objects with digital holography

Digital holography has some desirable properties for refractometry of microscopic objects since it gives phase and amplitude information of an object in all depths of focus from one set of exposures. We show that the amplitude part of the image can be used to observe how the Becke lines move between different depths of focus and hence determine whether an object has a higher or a lower index of re

Documentation of the physical properties of annually laminated (varved) sediments at a sub-annual to decadal resolution for environmental interpretation

This paper describes a method to digitize high-resolution physical properties of annually laminated lake sediments. We modified a water-acetone epoxy exchange method in order to preserve all the fine structural details that varved sequences provide. By applying sediment microstratigraphical investigations (X-ray radiography, SEM) and semi-automatic image analysis, we were able to establish detaile

Effects of waterfowl and fish on submerged vegetation and macroinvertebrates

1. With the aim to assess the combined and separate effects of waterfowl and fish on submerged vegetation and macroinvertebrates, we performed a replicated selective exclosure study in a shallow, eutrophic lake in southern Sweden. Our results are presented together with a literature review of the effects of fish and waterfowl on macroinvertebrates and submerged vegetation. 2. Based on our experime

Effects of systematic exposure assessment errors in partially ecologic case-control studies.

BACKGROUND: In ecologic studies, group-level rather than individual-level exposure data are used. When using group-level exposure data, established by sufficiently large samples of individual exposure assessments, the bias of the effect estimate due to sampling errors or random assessment errors at the individual-level is generally negligible. In contrast, systematic assessment errors may produce

Amperometric monitoring of redox activity in living yeast cells: comparison of menadione and menadione sodium bisulfite as electron transfer mediators

An amperometric method was applied for real-time monitoring of intracellular redox enzyme activity. Baker’s yeast (Saccharomyces cerevisiae) cells were immobilized on platinum microband electrodes and mediated anodic currents were measured. The currents were observed in the absence and in the presence of glucose as a source of reducing equivalents, NADH and NADPH. 2-Methyl-1,4-naphthoquinone (mena

Fibre type composition of rabbit tibialis anterior and extensor digitorum longus muscles

Rabbit tibialis anterior (TA) and extensor digitorum longus (EDL) muscles are used extensively in studies of stimulation-induced fibre type transformation, but the proportions and sizes of the 2 main fibre types, and the way in which they are distributed within the muscles, have never been described in any detail. In this study, transverse sections were processed by enzyme histochemical and immuno

Faint stars in the Ursa Minor dwarf spheroidal galaxy: implications for the low-mass stellar initial mass function at high redshift

The stellar initial mass function at high redshift is an important defining property of the first stellar systems to form and may also play a role in various dark matter problems. We here determine the faint stellar luminosity function in an apparently dark-matter-dominated external galaxy in which the stars formed at high redshift. The Ursa Minor dwarf spheroidal galaxy is a system with a particu

Association between inflammation and epithelial damage-restitution processes in allergic airways in vivo

BACKGROUND: Associations between allergen challenge-induced sites of epithelial damage and the distribution of leucocytes and extravasated plasma remain unexplored. OBJECTIVE: To study neutrophils, eosinophils, and fibrinogen at allergen challenge-induced patchy epithelial damage-restitution sites in guinea-pig trachea. METHODS: After local challenge tracheal tissue (cryo sections and whole-mounts

Retrovirally delivered Islet-1 increases recruitment of Ng2 expressing cells from the postnatal SVZ into the striatum.

Neural stem and progenitor cells hold the promise to be used in cell-based therapies to treat both acute and degenerative neurological diseases. To date, most research has been focused on the use of in vitro propagated stem cells used as a source of cells in cell replacement therapies. However, mobilization of endogenous neural stem cells to generate a specific differentiated cell type offers an a

Self-assembly of mixed ionic and zwitterionic amphiphiles: Associative and dissociative interactions between lamellar phases

The phase behavior and phase structure of the mixed lecithin/DDAB system in water are studied by SAXS, H-2 NMR, cryo-TEM, and optical polarization microscopy methods. Macroscopically, the triangular phase diagram is dominated by one lamellar liquid crystalline region. SAXS data in combination with 2H NMR detect the presence of two different lamellar phases. The collapsed lamellar phase originated

Human antibody response towards the pneumococcal surface proteins PspA and PspC during invasive pneumococcal infection.

gG antibodies against pneumococcal surface protein A, family 1 (PspAl) and family 2 (PspA2), protein C (PspC), and protein Hic were investigated in 41 patients with invasive pneumococcal disease. Pre-existing antibody levels against the four pneumococcal proteins were not significantly different from those found in 40 patients with non-pneumococcal bacteremia or 80 healthy controls. However, durin

Effects of a supplementary diet with specially processed cereals in patients with short bowel syndrome

Objective Short bowel syndrome patients frequently experience impaired health-related quality of life. This syndrome is also associated with increased costs for the individuals concerned and the community. Intake of specially processed cereals has been demonstrated to decrease intestinal secretion. This study evaluates the effect of a supplementary diet with specially processed cereals compared wi

Juvenile-hormone-mediated plasticity of aggregation behaviour and olfactory processing in adult desert locusts

In desert locusts Schistocerca gregaria, aggregation behaviour is elicited by aggregation pheromones. In this study, we show that the behavioural response to the major and most potent adult aggregation pheromone component, phenylacetonitrile, is age- and juvenile-hormone-dependent. Furthermore, we show that juvenile hormone influences the responsiveness of olfactory interneurons in the antennal lo

Fermentation performance of engineered and evolved xylose-fermenting Saccharomyces cerevisiae strains

Lignocellulose hydrolysate is an abundant substrate for bioethanol production. The ideal microorganism for such a fermentation process should combine rapid and efficient conversion of the available carbon sources to ethanol with high tolerance to ethanol and to inhibitory components in the hydrolysate. A particular biological problem are the pentoses, which are not naturally metabolized by the mai