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We present the first quantitative attempt at reconciling the source and emplacement of granite erratics in Beacon Valley. The erratics are enigmatic because granite does not crop out in the valley and its nearest subaerial exposure is at least 10 km downstream to the east of the valley. Detailed mapping of the valley shows three types of granite erratics, which are not present in equal amounts and do not show spatial patterns. Pb isotopic and elemental compositions of the erratics eliminate the Metschel Tillite as a source and indicate they derive from the Dry Valley plutons. Our limited study tentatively ties the erratics to suites of plutons, but it does not allow a direct tie of the erratics to specific plutons because of i) the geochemical variability of the plutons and ii) the limited number of erratics that were analysed. Published data suggest the erratics provide evidence of wet-based glaciation, which covered the Dry Valleys and much of Antarctica during the mid-Miocene. Our paper also explains the problems associated with the emplacement of these erratics and the age of the massive ice in Beacon Valley.
Using our semi-linear inversion method, we measure the mass profile of the lens galaxy in the Einstein ring system 0047–2808. The lens is modeled as a baryonic component following the observed light embedded in a generalised dark matter NFW halo. The semi-linear method makes full use of the information content in the ring image. We determine a B-band mass to light ratio for the baryons of 2.33+0.30–0.62h M⊙/LB⊙ (99% CL), accounting for 54% of the total projected mass within the Einstein radius of 1.16″. The inner logarithmic slope of the halo is found to be 0.65+0.73–0.31 (99% CL). We find that the halo is fairly well aligned with the light but has only half the ellipticity.
Objectives: The objective of this study was to compare evidence requirements for health technology assessment of pharmaceuticals by national agencies across Europe responsible for reimbursement decisions focusing specifically on relative effectiveness assessment.
Methods: Evidence requirements from thirty-three European countries were requested and twenty-nine national agencies provided documents to review. Data were extracted from national documents (manufacturer's submission templates and associated guidance) into a purpose-made framework with categories covering information about the health condition, the technology, clinical effectiveness and safety.
Results: The level of detail in the required evidence varies considerably across countries. Some countries include specific questions while others request information under general headings. Some countries include all information in a single document, which may or may not include guidance on how to complete the template. Others have specific guidance documents or methods and process manuals that help with the completion of the submission templates. Despite differences in quantity and detail, the content of the evidence requirements is broadly similar. All countries ask for information on the health technology, target disease, and clinical effectiveness and safety. However, one country only requests clinical effectiveness information as part of cost-effectiveness analyses. We found twenty-six evidence requirements for which generic answers may apply across borders and nineteen in which countries requested nationally specific information.
Conclusions: This work suggests that it would be possible to put together a minimum set of evidence requirements for HTA to support reimbursement decisions across Europe which could facilitate collaboration between jurisdictions.
In nerve and muscle regeneration applications, the incorporation of conducting elements into biocompatible materials has gained interest over the last few years, as it has been shown that electrical stimulation of some regenerating cells has a positive effect on their development. A variety of different materials, ranging from graphene to conducting polymers, have been incorporated into hydrogels and increased conductivities have been reported. However, the majority of conductivity measurements are performed in a dry state, even though material blends are designed for applications in a wet state, in vivo environment. The focus of this work is to use polypyrrole nanoparticles to increase the wet–state conductivity of alginate to produce a conducting, easily processable, cell–supporting composite material. Characterization and purification of the conducting polymer nanoparticle dispersions, as well as electrochemical measurements, have been performed to assess conductivity of the nanoparticles and hydrogel composites in the wet state, in order to determine whether filling an ionically conducting hydrogel with electrically conductive nanoparticles will enhance the conductivity. It was determined that the introduction of spherical nanoparticles into alginate gel does not increase, but rather slightly reduces conductivity of the hydrogel in the wet state.
We report on the electrical and structural properties of boron-doped diamond tips commonly used for in-situ electromechanical testing during nanoindentation. The boron dopant environment, as evidenced by cathodoluminescence (CL) microscopy, revealed significantly different boron states within each tip. Characteristic emission bands of both electrically activated and nonelectrically activated boron centers were identified in all boron-doped tips. Surface CL mapping also revealed vastly different surface properties, confirming a high amount of nonelectrically activated boron clusters at the tip surface. Raman microspectroscopy analysis showed that structural characteristics at the atomic scale for boron-doped tips also differ significantly when compared to an undoped diamond tip. Furthermore, the active boron concentration, as inferred via the Raman analysis, varied greatly from tip-to-tip. It was found that tips (or tip areas) with low overall boron concentration have a higher number of electrically inactive boron, and thus non-Ohmic contacts were made when these tips contacted metallic substrates. Conversely, tips that have higher boron concentrations and a higher number of electrically active boron centers display Ohmic-like contacts. Our results demonstrate the necessity to understand and fully characterize the boron environments, boron concentrations, and atomic structure of the tips prior to performing in situ electromechanical experiments, particularly if quantitative electrical data are required.
Canadian Cardiovascular Society consensus guidelines recommend that tetralogy of Fallot patients be seen by a congenital cardiologist every 2 years. In Atlantic Canada, tetralogy of Fallot patients are followed up at either tertiary or satellite clinics, which are held in the community and attended by paediatric cardiologists. The effectiveness of satellite clinics in congenital cardiac disease follow-up is unproven. Our objective was to compare patient-reported quality of life measures to determine whether these were impacted by the site of follow-up.
We included patients with tetralogy of Fallot undergoing surgical repair at the Izaak Walton Killam Health Centre from 1 November, 1972 to 31 May, 2002. Quality of life surveys, SF-10 or SF-36v2, were administered to consenting patients. We analysed the subjective health status by patient age and site of follow-up.
Of the 184 eligible patients, 72 were lost to follow-up. Of the locatable patients, 61% completed the questionnaires. In all, 90% (101 out of 112) were followed up at recommended intervals. Of the 112 (68%) patients, 76 were followed up at a tertiary clinic. These patients were older, with a mean age of 18.4 years versus 14.7 years, and scored higher on the SF-36 physical component summary (52.6 versus 45.7, p = 0.02) compared with satellite clinic patients. The SF-36 mental component summary scores were similar for patients regardless of the site of follow-up. SF-10 physical and psychosocial scores were similar regardless of the site of follow-up.
Tetralogy of Fallot patients followed at either satellite or tertiary clinics have similar subjective health status.
Phase transformed zones of silicon have been formed by nanoindentation both at the micro- and nanoscale and electrically probed using an in-situ measurement system. Zones composed of the high pressure crystalline phases (Si-III/Si-XII) have higher conductivity than those of amorphous silicon (a-Si). At the microscale probing laterally across the surface shows that the conductivity varies within the zones composed of the high pressure phases. The sensitivity to the different conductivities of the two phases allows mapping within the zones. Finally, at the nanoscale the conductivity of the high pressure phase zones can be correlated with the position of the pop-out associated with the formation of the phases. The zones have higher conductivity when the pop-out occurs earlier on unloading and we suggest that this is due to the reduction in trace volumes of a-Si formed during the early portion of the unloading cycle.
We sought to determine the frequency with which fellows in accredited Canadian pediatric emergency medicine (PEM) fellowships perform specific procedures, the level of confidence fellows have in their abilities and whether there are differences in self-perceived success between first- and second-year fellows.
A national survey was developed that focused on 24 PEM procedural skills. The survey asked respondents how many times they had performed these procedures within the past 12 months and within the past 3 years. Respondents were then asked to rate their confidence in successfully performing each of the 24 procedures.
Of the 46 surveys sent to PEM fellows, 32 (70%) were returned. Most respondents were in their second year of training and the vast majority had previous training in pediatrics. In order of frequency, the most common procedures performed were closed reduction of fractures, peripheral intravenous insertion, complex laceration repair and endotracheal intubation. Of the surveyed skills, oropharyngeal/nasopharyngeal airway insertion was deemed the most successful (100% success rate for second-year fellows v. 92.5% success rate for first-year fellows, p = 0.01). Similarly, second-year fellows had a higher self-perceived success rate for intraosseous line insertion than did first-year fellows (95.0% v. 80.0% for second- and first-year fellows, respectively, p < 0.001).
In surveying PEM trainees across Canada, we have described the frequency and self-perceived success rate for 24 important procedures. This information may be helpful for program directors in evaluating future directions and opportunities for training of their PEM trainees.
To compare the effects of hospital cleaning agents and germicides on the survival of epidemic Clostridium difficile strains.
We compared the activity of and effects of exposure to 5 cleaning agents and/or germicides (3 containing chlorine, 1 containing only detergent, and 1 containing hydrogen peroxide) on vegetative and spore forms of epidemic and non-epidemic C. difficile strains (3 of each). We carried out in vitro exposure experiments using a human fecal emulsion to mimic conditions found in situ.
Cleaning agent and germicide exposure experiments yielded very different results for C. difficile vegetative cells, compared with those for spores. Working-strength concentrations of all of the agents inhibited the growth of C. difficile in culture. However, when used at recommended working concentrations, only chlorine-based germicides were able to inactivate C. difficile spores. C. difficile epidemic strains had a greater sporulation rate than nonepidemic strains. The mean sporulation rate, expressed as the proportion of a cell population that is in spore form, was 13% for all strains not exposed to any cleaning agent or germicide, and it was significantly increased by exposure to cleaning agents or germicides containing detergent alone (34%), a combination of detergent and hypochlorite (24%), or hydrogen peroxide (33%). By contrast, the mean sporulation rate did not change substantially after exposure to germicides containing either a combination of detergent and dichloroisocyanurate (9%) or dichloroisocyanurate alone (15%).
These results highlight differences in the activity of cleaning agents and germicides against C. difficile spores and the potential for some of these products to promote sporulation.
We give a non-exhaustive review of the use of strong gravitational lensing in placing constraints on the quantity of dark and visible mass in galaxies. We discuss development of the methodology and summarise some recent results.