Reproducibility of electrical caries measurements: A technical problem?

The currently available instrument for electrical detection of occlusal caries lesions {[}Electronic Caries Monitor (ECM)] uses a site-specific measurement with co-axial air drying. The reproducibility of this method has been reported to be fair to good. It was noticed that the measurement variation of this technique appeared to be non-random. It was the aim of this study to analyse how such a non-random reproducibility pattern arises and whether it could be observed for other operators and ECM models. Analysis of hypothetical measurement pairs showed that the pattern was related to measurements at the high and low end of the measurement range for the instrument. Data sets supplied by other researchers to a varying degree showed signs of a similar non-random pattern. These data sets were acquired at different locations, by different operators and using 3 different ECM models. The frequency distribution of measurements in all cases showed a single or double end-peaked distribution shape. It was concluded that the pattern was a general feature of the measurement method. It was tentatively attributed to several characteristics such as a high value censoring, insufficient probe contact and unpredictable probe contact. A different measurement technique, with an improved probe contact, appears to be advisable. Copyright (C) 2005 S. Karger AG, Basel

Deepening, Broadening and Scaling up: a Framework for Steering Transition Experiments.

This essay presents a conceptual framework for analyzing and influencing the contribution of small-scale experiments to transitions towards a more sustainable society. This framework is aimed at providing academics and practitioners with a theoretical and practice oriented perspective to both understand and ‘steer’ the contribution of experiments to transitions. The central instrument in this framework are ‘transition experiments’, which provide an alternative approach to classical innovation projects that are aimed at realizing short-term solutions. A transition experiment is an innovation project with a societal challenge as a starting point for learning aimed at contributing to a transition

Structure and reactivity of titania-supported oxides. Part 1: vanadium oxide on titania in the sub- and super-monolayer regions

Vanadium oxide has been deposited on TiO2 (washed anatase, 10 m2g−1; Degussa P-25, 55 ±3 m2g−1; Eurotitania, 46 m2g−1) by aqueous impregnation of (NH4)2[VO(C2O4)2] and by reaction with VOCl3, VO(OR)3 (R=iBu) and VO(acac)2 in organic solvents. Single applications of the last tree reagents form not more than a monolayer of vanadium oxide VOx, a monolayer being defined as 0.10 wt.% V2O5 per m2 of surface. When less than about four monolayers of VOx are present, there is in most cases only a single TPR peak: Tmax values, which increase with V2O5 content, are almost independent of the method used but vary slightly with the support (P-25 < Eurotitania < washed anatase). The 995 cm−1 band, characteristic of V&z.dbnd;O in V2O5, only appears when more than a monolayer of VOx is present.\ud \ud In the sub-monolayer region, VOx is best formulated as an oxohydroxy species bonded to two surface oxygens. As the V2O5 content is increased, layers of disordered V2O5 are formed on limited areas of the surface, but crystalline V2O5 only occurs, probably on top of the disordered V2O5, when the V2O5 content exceeds about four monolayers, and takes the form of acicular crystals exposing only planes perpendicular to the a and b axes

Modelling Data Pipelines

Data is the new currency and key to success. However, collecting high-quality data from multiple distributed sources requires much effort. In addition, there are several other challenges involved while transporting data from its source to the destination. Data pipelines are implemented in order to increase the overall efficiency of data-flow from the source to the destination since it is automated and reduces the human involvement which is required otherwise. Despite existing research on ETL (Extract-Transform-Load) and ELT (Extract-Load-Transform) pipelines, the research on this topic is limited. ETL/ELT pipelines are abstract representations of the end-to-end data pipelines. To utilize the full potential of the data pipeline, we should understand the activities in it and how they are connected in an end-to-end data pipeline. This study gives an overview of how to design a conceptual model of data pipeline which can be further used as a language of communication between different data teams. Furthermore, it can be used for automation of monitoring, fault detection, mitigation and alarming at different steps of data pipeline

Ambulance deceleration causes increased intra cranial pressure in supine position:a prospective observational proof of principle study

BACKGROUND: Ambulance drivers in the Netherlands are trained to drive as fluent as possible when transporting a head injured patient to the hospital. Acceleration and deceleration have the potential to create pressure changes in the head that may worsen outcome. Although the idea of fluid shift during braking causing intra cranial pressure (ICP) to rise is widely accepted, it lacks any scientific evidence. In this study we evaluated the effects of driving and deceleration during ambulance transportation on the intra cranial pressure in supine position and 30(°) upright position. METHODS: Participants were placed on the ambulance gurney in supine position. During driving and braking the optical nerve sheath diameter (ONSD) was measured with ultrasound. Because cerebro spinal fluid percolates in the optical nerve sheath when ICP rises, the diameter of this sheath will distend if ICP rises during braking of the ambulance. The same measurements were taken with the headrest in 30(°) upright position. RESULTS: Mean ONSD in 20 subjects in supine position increased from 4.80 (IQR 4.80–5.00) mm during normal transportation to 6.00 (IQR 5.75–6.40) mm (p < 0.001) during braking. ONSD’s increased in all subjects in supine position. After raising the headrest of the gurney 30(°) mean ONSD increased from 4.80 (IQR 4.67–5.02) mm during normal transportation to 4.90 (IQR 4.80–5.02) mm (p = 0.022) during braking. In 15 subjects (75%) there was no change in ONSD at all. CONCLUSIONS: ONSD and thereby ICP increases during deceleration of a transporting vehicle in participants in supine position. Raising the headrest of the gurney to 30 degrees reduces the effect of breaking on ICP

Central ions and lateral asparagine/glutamine zippers stabilize the post-fusion hairpin conformation of the SARS coronavirus spike glycoprotein

AbstractThe coronavirus spike glycoprotein is a class I membrane fusion protein with two characteristic heptad repeat regions (HR1 and HR2) in its ectodomain. Here, we report the X-ray structure of a previously characterized HR1/HR2 complex of the severe acute respiratory syndrome coronavirus spike protein. As expected, the HR1 and HR2 segments are organized in antiparallel orientations within a rod-like molecule. The HR1 helices form an exceptionally long (120 Å) internal coiled coil stabilized by hydrophobic and polar interactions. A striking arrangement of conserved asparagine and glutamine residues of HR1 propagates from two central chloride ions, providing hydrogen-bonding “zippers” that strongly constrain the path of the HR2 main chain, forcing it to adopt an extended conformation at either end of a short HR2 α-helix

Does disaster affect immigrant victims more than non-immigrant victims in Dutch general practice: a matched cohort study

Background: In the literature, immigrant victims appear to be more vulnerable to health effects of a disaster than indigenous victims. Most of these studies were performed without pre-disaster measurement and without using a control group. Aim: The objective of the study is to monitor differences between two groups of victims, Turkish immigrants and indigenous Dutch, in utilization and morbidity as presented in general practice after a man-made disaster. Methods: A matched cohort study was performed with pre-disaster (1 year) and post-disaster (4 years) measurements of patients from 30 general practices in Enschede. Turkish victims (N=303) and Dutch victims (N=606), matched on age, gender and socioeconomic status, were included. Main outcome measures were psychological problems and physical symptoms as recorded by the general practitioner, using the International Classification of Primary Care (ICPC). Results: The Turkish victims showed higher utilization than the Dutch victims prior to the disaster. In the 1st post-disaster year, both groups of victims showed an increase in utilization, but the increases did not differ significantly. The Turkish group showed no significantly greater increase than the Dutch group in the five most prevalent clusters of health problems (psychological, respiratory, skin, musculoskeletal, and digestive). Conclusion: The Turkish victims in general practice were as vulnerable as the Dutch victims for the effects on their health of this man-made disaster. Differences between Turkish and native Dutch victims of this man-made disaster can largely be explained by the differences that existed already before the disaster

PFGE diversity within the methicillin-resistant Staphylococcus aureus clonal lineage ST398

<p>Abstract</p> <p>Background</p> <p>Livestock has recently been identified as a new reservoir of methicillin-resistant <it>Staphylococcus aureus </it>(MRSA). Most isolates belong to ST398 and are non-typeable with PFGE using <it>Sma</it>I, making it difficult to study transmission and outbreaks. Therefore, a new PFGE using <it>Cfr</it>9I, a neoschizomer of <it>Sma</it>I was optimized and evaluated to investigate ST398 isolates.</p> <p>Results</p> <p>After optimizing and evaluating the <it>Cfr</it>9I PFGE, clear and reproducible banding patterns were obtained from all previously non-typeable MRSA (NT_{<it>Sma</it>I}-MRSA) isolates. The PFGE patterns of ST398 isolates showed more diversity than with <it>spa</it>-typing and/or MLST. The PFGE results showed diversity within and between the two most prevalent <it>spa</it>-types of NT_{<it>Sma</it>I}-MRSA (t011 and t108). No match was found, when comparing banding patterns of the NT_{<it>Sma</it>I}-MRSA with 700 different PFGE types, obtained with <it>Sma</it>I digestion, in our database of more than 4000 strains. Furthermore, possible transmission among veterinarians and their family members was investigated and an outbreak of ST398 MRSA in a residential care facility was confirmed with the <it>Cfr</it>9I PFGE.</p> <p>Conclusions</p> <p>The adjusted PFGE can be used as a method for selecting important and distinct ST398 isolates for further research. The adjustments in the PFGE protocol using <it>Cfr</it>9I are easy to implement to study the ST398 clonal lineage in laboratories which already have a PFGE facility.</p