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Surface science at MAX-LAB

The 550 MeV storage ring at MAX-LAB provides synchrotron radiation for a large community of users. An important part of the scientific program is photoelectron spectroscopy studies of semiconductor and metal surfaces and interfaces. Here is a brief review of some of the experimental efforts obtained in this area. Results are shown for the Ge(100)2×1:As, Si(111):Au, Mo(110):Yb and Mo(110):Sm system

Core-excitoninduced desorption from MgO

Core-exciton-induced desorption of O and H from MgO(100) and MgO(111) has been observed using photon excitation energies spanning the O K edge. Electron-yield data from partially oxidized Mg implies that these states are localized in the near-surface region. O and H desorption results from the decay of different O core-exciton states as well as the states produced by interband transitions. The O e

Effects of gastrin on calcium homeostasis in chickens

As in the rat, gastrin and an extract of the acid-producing part of the stomach (proventriculus) were found to lower the blood Ca2+ concentration in the chicken. Furthermore, gastrin enhanced the uptake of 45Ca into the femur. It has been suggested previously that gastrin causes hypocalcemia in the rat by releasing gastrocalcin, a hypothetical hormone thought to reside in the acid-producing part o

Gastrectomy causes bone loss in the rat: is lack of gastric acid responsible?

Total gastrectomy or resection of the acid-producing part of the stomach (fundectomy) in the rat induced a marked and rapid reduction in bone wet weight, ash weight, and density (expressed as ash weight in mg/mm3 bone). Bone volumes were also affected but not as much. The radius, sternum, tibia, and femur were studied. Three weeks after gastrectomy the bone ash weight was reduced by almost 30% and

Variety in knowledge sourcing, geography and innovation: Evidence from the ICT sector in Austria

It has been argued that innovation increasingly depends on external knowledge sources. It is still unclear if relations to particular knowledge sources or to a broad variety of sources matter for innovation. Also, there is a debate on the issue which spatial levels are most relevant. In this context, we investigate the importance for ICT firms in Austria of variety in knowledge sourcing for their

Growth of the parathyroid glands in omeprazole-treated chickens

BACKGROUND: Omeprazole, a long-acting inhibitor of gastric acid secretion, is able to increase the circulating concentrations of gastrin. Daily treatment with high doses of omeprazole cause sustained hypergastrinemia. Long-standing hypergastrinemia can be expected to exert numerous effects in the body. For instance, gastrin has been proposed to promote growth in the digestive tract and pancreas. T

Perturbations in blood Ca2+ do not affect the activity of rat stomach enterochromaffin-like cells.

BACKGROUND: Gastrin stimulates uptake of Ca(2)+ into bone and causes transient hypocalcemia, possibly by releasing a peptide hormone from enterochromaffin-like (ECL) cells, which are histamine- and peptidehormone-producing cells in the acid-producing part of the stomach. However, if ECL cells secrete a calciotropic hormone, it is to be expected that their activity is affected by the serum Ca(2)+ c

Extrapancreatic trypsin-2 cleaves proteinase-activated receptor-2.

Proteinase-activated receptors (PARs) are activated by proteolytic removal of a short amino terminal peptide, thus exposing a new amino terminus that functions as a tethered ligand that activates the receptor. With the aim to identify and study potential activators of PAR-2 we have developed a new method to measure proteolytic cleavage of PARs. PAR-2 was tagged with the insulin C-peptide that upon

Empowering interviews : narrative interviews in the study of information literacy in everyday life settings

The main aim of this paper is to discuss how, within a sociocultural perspective, to design and conduct interviews for studying information literacy in everyday life. A methodological framework combining a sociocultural perspective with a narrative interview method is developed, in which visual tools are used to engage interviewees as active participants in the interview situation. This method was

Gender differences in knee abduction during weight-bearing activities : A systematic review and meta-analysis

Background Increased knee abduction during weight-bearing activities is suggested to be a contributing factor for the high knee injury risk reported in women. However, studies investigating gender difference in knee abduction are inconclusive. Objective To systematically review gender-differences in knee abduction during weight-bearing activities in individuals with or without knee injury. Methods

Value creation character and value assessment responsibility

Value-based pricing is by many companies as well as in academia perceived as the preferred pricing model. The pricing literature includes a long-standing debate on pricing authority and centralized pricing authority can be associated with value-based pricing strategies. A critical success factor for value-based pricing is customer value assessment, and many companies have experienced challenges in

Beta-delayed proton emission from 20Mg

Beta-delayed proton emission from 20 Mg has been measured at ISOLDE, CERN, with the ISOLDE Decay Station (IDS) setup including both charged-particle and gamma-ray detection capabilities. A total of 27 delayed proton branches were measured including seven so far unobserved. An updated decay scheme, including three new resonances above the proton separation energy in 20 Na and more precise resonance

Colocalization of (3H)-adenosine accumulation and GABA immunoreactivity in the chicken and rabbit retinas

Using combined autoradiography and immunohistochemistry, we have compared (3H)-adenosine accumulation and GABA immunoreactivity in the chicken and rabbit retinas. Colocalization of the two markers was observed in a subset of amacrine cells and in certain cell bodies in the ganglion cell layer in both species and in a few horizontal cells in the chicken retina. Cells that contained only (3H)-adenos

Provenance does matter : links between winter trophic segregation and the migratory origins of European robins

Amongst migratory species, it is common to find individuals from different populations or geographical origins sharing staging or wintering areas. Given their differing life histories, ecological theory would predict that the different groups of individuals should exhibit some level of niche segregation. This has rarely been investigated because of the difficulty in assigning migrating individuals

Monitoring dioxins in food and feedstuffs using accelerated solvent extraction with a novel integrated carbon fractionation cell in combination with a CAFLUX bioassay

The concentrations of dioxins in fish oil and fish meal were determined with accelerated solvent extraction, using a novel integrated carbon fractionation extraction cell followed by a miniturized multilayer silica column and bioanalysis on a recently-developed chemically-activated fluorescent gene expression cell bioassay. The developed method allows for simultaneous gravimetric lipid weight dete