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Investigation of the bond strength between the photo-sensitive polymer SU-8 and gold

We present the results from a thorough investigation of the bond strength between the photo-polymer SU-8 and Au. The data were obtained by pull-test experiments, below the glass transition temperature of the polymer. The different aspects that we investigated were: (i) the effect of using different adhesion promoters between the SU-8 and Au; (ii) the influence of the processing sequence, keeping e

Rogen moraine: an example of glacial reshaping of pre-existing landforms

Rogen moraine is widely distributed in the core areas of the former Scandinavian and Laurentide ice sheets. It is generally agreed upon that these gently arched, ice-How transverse ridges call be used in reconstructions of paleo-ice-flow patterns and that they indicate a melted-bed or poly-thermal basal ice regime. However, the processes of ridge generation have been contentious. This study propos

Functional effects of the inhibition of the cysteine protease activity of the major house dust mite allergen Der p 1 by a novel peptide-based inhibitor

BACKGROUND: The house dust mite (HDM) Dermatophagoides pteronyssinus is an important source of allergens, which can cause allergic conditions. The cysteine protease activity of Der p 1 may enhance the potency of this major mite allergen through cleavage of CD23 and CD25 from the surface of immune cells, IgE independent mast cell activation, increases in epithelial cell permeability and inactivatio

Purification of truncated and mutated chemotaxis inhibitory protein of Staphylococcus aureus—an anti-inflammatory protein

The Chemotaxis Inhibitory Protein of Staphylococcus aureus (CHIPS) binds and blocks the C5a receptor (C5aR) and formyl-peptide receptor (FPR). This way, CHIPS is a potent inhibitor of the immune cell recruitment associated with inflammation. Truncation of the protein and the introduction of mutations, shifts the expression towards the insoluble fraction of Escherichia coli, whereas the wild-type p

Evaluation of nasal barrier dysfunction at acute- and late-phase reactions in a guinea pig model of allergic rhinitis

Allergic rhinitis is a common disease characterized by the symptoms of pruritus, sneezing, hypersecretion and nasal blockage. Increased mucosal barrier permeability has been suggested to be an indicator for the severity of allergic rhinitis. This study investigates the passage of radiolabelled albumin from the nasal mucosal circulation into the lumen in guinea pigs intraperitoneally sensitized and

Influence of cell shape and aggregate formation on the optical properties of flowing whole blood

We studied the influence of shape and secondary, or intercellular, organization on the absorption and scattering properties of red blood cells to determine whether these properties are of any practical significance for optical evaluation of whole blood and its constituents. A series of measurements of transmittance and reflectance of light from bovine blood in a flow cuvette was conducted with a 6

Past occurrences of hypoxia in the Baltic Sea and the role of climate variability, environmental change and human impact

The hypoxic zone in the Baltic Sea has increased in area about four times since 1960 and widespread oxygen deficiency has severely reduced macro benthic communities below the halocline in the Baltic Proper and the Gulf of Finland, which in turn has affected food chain dynamics, fish habitats and fisheries in the entire Baltic Sea. The cause of increased hypoxia is believed to be enhanced eutrophic

Development of Duffy transgenic mouse: in vivo expression of human Duffy gene with -33T -> C promoter mutation in non-erythroid tissues

Blood group Duffy gene (FY) promoter in Duffy-negative individuals contains a point mutation in the GATA1 protein-binding motif, which was suggested to be responsible for erythroid suppression of FY. We developed two transgenic mouse lines with FY from both Duffy phenotypes. Transgenic mice with FY from Duffy-positive phenotype expressed Duffy protein both in red blood cells (RBCs) and non-erythro

Heterotrophic bacterial and viral dynamics in Arctic freshwaters: results from a field study and nutrient-temperature manipulation experiments

Heterotrophic bacterial and viral concentrations (range, 0.7 x 10(4) to 206.2 x 10(4) ml(-1) and 0.05 x 10(6) to 128.9 x 10(6) ml(-1), respectively) were determined in several Arctic freshwater environments, including lakes and glacial ecosystems (78.55 degrees N, 11.56 degrees E). Our bacteria and virus results mirrored trends seen in temperate lakes, with an average virus-to-bacteria ratio (VBR)

Molecular alignment of ammonia studied by electron-ion-ion coincidence spectroscopy

Electron-ion-ion coincidence measurements carried out at discrete resonances near the N 1s threshold in ammonia are reported. The measured coincidence spectra show clear alignment of the molecule upon resonant core-electron excitation. The coincidence data are analyzed to extract information about the molecule in the excited state by simulating the alignment and the dissociation processes. Dynamic

Improved spectrophotometric vitellogenin determination via alkali-labile phosphate in fish plasma - a cost effective approach for assessment of endocrine disruption

Vitellogenin (VTG) is a well known protein biomarker for exposure to environmental estrogens and possible endocrine disruption in fish. VTG is very dominant in plasma after the onset of vitellogenesis and the protein is heavily phosphorylated. This enables indirect quantification through measurement of alkali-labile protein bound phosphate (ALP) as an alternative to the more expensive enzyme linke

Embedding point sets into plane graphs of small dilation

Let S be a set of points in the plane. What is the minimum possible dilation of all plane graphs that contain S? Even for a set S as simple as five points evenly placed on the circle, this question seems hard to answer; it is not even clear if there exists a lower bound >1. In this paper we provide the first upper and lower bounds for the embedding problem. 1. Each finite point set can be embedded

Screen-printed multienzyme arrays for use in amperometric batch and flow systems

Screen-printing technology for electrode fabrication enables construction of amperometric devices suitable for combination of several enzyme electrodes. To develop a biosensor array for characterisation of wastewaters, tyrosinase and horseradish peroxidase (HRP) or cholinesterase-modified electrodes were combined on the same array. The behaviour of the tyrosinase-modified electrode in the presence

Calbindin D-28k EF-hand ligand binding and oligomerization: Four high-affinity sites-three modes of action

Calbindin D-28k, a highly conserved protein with Ca2+-sensing and Ca2+-buffering capabilities, is abundant in brain and sensory neurons. This protein contains six EF-hand subdomains, four of which bind Call with high affinity. Calbindin D28k can be reconstituted from six synthetic peptides corresponding to the six EF-hands, indicating a single-domain structure with multiple interactions between th

T-cell tolerance induced by repeated antigen stimulation: Selective loss of Foxp3(-) conventional CD4 T cells and induction of CD4 T-cell anergy.

Repeated immunization of mice with bacterial superantigens induces extensive deletion and anergy of reactive CD4 T cells. Here we report that the in vitro proliferation anergy of CD4 T cells from TCR transgenic mice immunized three times with staphylococcal enterotoxin B (SEB) (3x SEB) is partially due to an increased frequency of Foxp3(+) CD4 T cells. Importantly, reduced number of conventional C