Noncyclic mixed state phase in SU(2) polarimetry

We demonstrate that Pancharatnam's relative phase for mixed spin$-{1/2}$ states in noncyclic SU(2) evolution can be measured polarimetrically.Comment: References update, journal reference adde

Evaluation of BART for measuring available bandwidth in an industrial application

We report results from a field study using the BART method for measuring available bandwidth in a local IP-network for use in train cars. The test was performed on physical hardware in a laboratory environment for a set of two cars. Test results indicate that BART measurement is viable

ECL Cell Histamine Mobilization Studied byGastric Submucosal Microdialysis in Awake Rats:Methodological Considerations.

The ECL cells are endocrine/paracrine cells in the acid-producing part of the stomach. They secrete histamine in response to circulating gastrin. Gastric submucosal microdialysis has been used to study ECL-cell histamine mobilization in awake rats. In the present study we assess the usefulness and limitations of the technique. Microdialysis probes were implanted in the gastric submucosa. Histological analysis of the stomach wall around the probe revealed a moderate, local inflammatory reaction 1-2 days after implantation; the inflammation persisted for at least 10 days. Experiments were conducted 3 days after the implantation. The "true" submucosal histamine concentration was determined by perfusing at different rates (the zero flow method) or with different concentrations of histamine at a constant rate (the no-net-flux method): in fasted rats it was calculated to be 87±5 (means±S.E.M.) nmol/l and 76±9 nmol/l, respectively. The corresponding histamine concentrations in fed rats were 93±5 and 102±8 nmol/l, respectively. With a perfusion rate of 74 mul/hr the recovery of submucosal histamine was 49%, at 34 mul/hr the recovery increased to 83%. At a perfusion rate below 20 mul/hr the microdialysate histamine concentration was close to the actual concentration in the submucosa. The ECL-cell histamine mobilization was independent of the concentrations of Ca2+ in the perfusion medium (0-3.4 mmol/l Ca2+). In one experiment, histamine mobilization in response to gastrin (10 nmol/kg/hr subcutaneously) was monitored in rats pretreated with prednisolone (60 mg/kg) or indomethacin (15 mg/kg). The two antiinflammatory agents failed to affect the concentration of histamine in the microdialysate either before or during the gastrin challenge, which was in accord with the observation that the inflammatory reaction was modest and that inflammatory cells were relatively few around the probe and in the wall of the probe. In another experiment, rats were given aminoguanidine (10 mg/kg) or metoprine (10 mg/kg) 4 hr before the start of gastrin infusion (5 nmol/kg/hr intravenously). Metoprine (inhibitor of histamine N-methyl transferase) did not affect the microdialysate histamine concentration, while aminoguanidine (inhibitor of diamine oxidase) raised both basal and gastrin-stimulated histamine concentrations. We conclude that microdialysis can be used to monitor changes in the concentration of histamine in the submucosa of the stomach, and that the inflammatory reaction to the probe is moderate and does not affect the submucosal histamine mobilization

Does chess need intelligence? – A study with young chess players

Although it is widely acknowledged that chess is the best example of an intellectual activity among games, evidence showing the association between any kind of intellectual ability and chess skill has been remarkably sparse. One of the reasons is that most of the studies investigated only one factor (e.g., intelligence), neglecting other factors relevant for the acquisition of chess skill (e.g., amount of practice, years of experience). The present study investigated the chess skill of 57 young chess players using measures of intelligence (WISC III), practice, and experience. Although practice had the most influence on chess skill, intelligence explained some variance even after the inclusion of practice. When an elite subsample of 23 children was tested, it turned out that intelligence was not a significant factor in chess skill, and that, if anything, it tended to correlate negatively with chess skill. This unexpected result is explained by a negative correlation between intelligence and practice in the elite subsample. The study demonstrates the dangers of focusing on a single factor in complex real-world situations where a number of closely interconnected factors operate

Status Report on the Application of Integrated Approaches to Water Resources Management 2012

UN-Water produced a status report regarding the progress of water resources management in several countries as well as possible outcomes and impacts of integrated approaches. It is also based on a 2011 UN-Water survey sent to the governments of all UN member states and a series of complementary interviews in 30 representative countries

Developmental origins and evolution of jaws: new interpretation of “maxillary” and “mandibular”

AbstractCartilage of the vertebrate jaw is derived from cranial neural crest cells that migrate to the first pharyngeal arch and form a dorsal “maxillary” and a ventral “mandibular” condensation. It has been assumed that the former gives rise to palatoquadrate and the latter to Meckel's (mandibular) cartilage. In anamniotes, these condensations were thought to form the framework for the bones of the adult jaw and, in amniotes, appear to prefigure the maxillary and mandibular facial prominences. Here, we directly test the contributions of these neural crest condensations in axolotl and chick embryos, as representatives of anamniote and amniote vertebrate groups, using molecular and morphological markers in combination with vital dye labeling of late-migrating cranial neural crest cells. Surprisingly, we find that both palatoquadrate and Meckel's cartilage derive solely from the ventral “mandibular” condensation. In contrast, the dorsal “maxillary” condensation contributes to trabecular cartilage of the neurocranium and forms part of the frontonasal process but does not contribute to jaw joints as previously assumed. These studies reveal the morphogenetic processes by which cranial neural crest cells within the first arch build the primordia for jaw cartilages and anterior cranium

Zebularine induces long-term survival of pancreatic islet allotransplants in streptozotocin treated diabetic rats.

Coping with the immune rejection of allotransplants or autologous cells in patients with an active sensitization towards their autoantigens and autoimmunity presently necessitates life-long immune suppressive therapy acting on the immune system as a whole, which makes the patients vulnerable to infections and increases their risk of developing cancer. New technologies to induce antigen selective long-lasting immunosuppression or immune tolerance are therefore much needed

Boganmeldelser

Book review

Qualitative research design and approaches in radiography

Introduction Radiography, as with other health care professions, aims towards establishing full professional recognition. A recognized research background is considered an essential component of this. Usually, emphasis is placed on quantitative research which focuses on the deductive component of the scientific 'confirmatory' method. However, this situation changed after the emergence of a post-positivist philosophy of medical research, which suggests the need for both quantitative and qualitative research to grasp a better understanding of the reality. The nature of qualitative research, unlike quantitative, is inductive and exploratory, providing insight into certain topics of which little is known and hence complementing quantitative research. Purpose: This article identifies the main qualitative research traditions that can be applied to radiography, providing a review in terms of their applications, areas of inquiry, and strengths and weaknesses according to the nature of the study. Previous radiography studies using qualitative approaches are critically reviewed to illustrate these issues. Their applications are also discussed based on the proposed radiography research framework by Adams and Smith, who identified broad radiography research areas aiming to further the research capacity of radiographers and the profession, especially by means of qualitative research.Methods: A comprehensive literature search was conducted using the CINAHL and ScienceDirect databases and the journal Radiography, and by using the keywords qualitative research to identify articles focusing on qualitative research. Only articles that were related to health care disciplines were then selected for the review. Conclusion: Three approaches, that are grounded theory, phenomenology and ethnography, can all be applied to the proposed radiography research framework to study intra- and inter-professional issues and clinical practice, and patient and health delivery issues. Hence, qualitative research methods can be used to rigorously study these important areas so as to produce high quality outcomes and promote the use of qualitative approaches in the radiography research culture