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Three-dimensional printing is increasingly utilised for congenital heart defect procedural planning. CT or MR datasets are typically used for printing, but similar datasets can be obtained from three-dimensional rotational angiography. We sought to assess the feasibility and accuracy of printing three-dimensional models of CHD from rotational angiography datasets.
Retrospective review of CHD catheterisations using rotational angiography was performed, and patient and procedural details were collected. Imaging data from rotational angiography were segmented, cleaned, and printed with polylactic acid on a Dremel® 3D Idea Builder (Dremel, Mount Prospect, IL, USA). Printing time and materials’ costs were captured. CT scans of printed models were compared objectively to the original virtual models. Two independent, non-interventional paediatric cardiologists provided subjective ratings of the quality and accuracy of the printed models.
Rotational angiography data from 15 catheterisations on vascular structures were printed. Median print time was 3.83 hours, and material costs were $2.84. The CT scans of the printed models highly matched with the original digital models (root mean square for Hausdorff distance 0.013 ± 0.003 mesh units). Independent reviewers correctly described 80 and 87% of the models (p = 0.334) and reported high quality and accuracy (5 versus 5, p = NS; κ = 0.615).
Imaging data from rotational angiography can be converted into accurate three-dimensional-printed models of CHD. The cost of printing the models was negligible, but the print time was prohibitive for real-time use. As the speed of three-dimensional printing technology increases, novel future applications may allow for printing patient-specific devices based on rotational angiography datasets.
Clostridium difficile, the most common cause of hospital-associated diarrhoea in developed countries, presents major public health challenges. The high clinical and economic burden from C. difficile infection (CDI) relates to the high frequency of recurrent infections caused by either the same or different strains of C. difficile. An interval of 8 weeks after index infection is commonly used to classify recurrent CDI episodes. We assessed strains of C. difficile in a sample of patients with recurrent CDI in Western Australia from October 2011 to July 2017. The performance of different intervals between initial and subsequent episodes of CDI was investigated. Of 4612 patients with CDI, 1471 (32%) were identified with recurrence. PCR ribotyping data were available for initial and recurrent episodes for 551 patients. Relapse (recurrence with same ribotype (RT) as index episode) was found in 350 (64%) patients and reinfection (recurrence with new RT) in 201 (36%) patients. Our analysis indicates that 8- and 20-week intervals failed to adequately distinguish reinfection from relapse. In addition, living in a non-metropolitan area modified the effect of age on the risk of relapse. Where molecular epidemiological data are not available, we suggest that applying an 8-week interval to define recurrent CDI requires more consideration.
To determine the patterns and predictors of treatment response trajectories for veterans with post-traumatic stress disorder (PTSD).
Conditional latent growth mixture modelling was used to identify classes and predictors of class membership. In total, 2686 veterans treated for PTSD between 2002 and 2015 across 14 hospitals in Australia completed the PTSD Checklist at intake, discharge, and 3 and 9 months follow-up. Predictor variables included co-morbid mental health problems, relationship functioning, employment and compensation status.
Five distinct classes were found: those with the most severe PTSD at intake separated into a relatively large class (32.5%) with small change, and a small class (3%) with a large change. Those with slightly less severe PTSD separated into one class comprising 49.9% of the total sample with large change effects, and a second class comprising 7.9% with extremely large treatment effects. The final class (6.7%) with least severe PTSD at intake also showed a large treatment effect. Of the multiple predictor variables, depression and guilt were the only two found to predict differences in response trajectories.
These findings highlight the importance of assessing guilt and depression prior to treatment for PTSD, and for severe cases with co-morbid guilt and depression, considering an approach to trauma-focused therapy that specifically targets guilt and depression-related cognitions.
Transcatheter pulmonary valve implantation is usually performed from a femoral venous – transfemoral – approach, but this may not be the optimal vascular access option in some patients. This study aimed to determine which group of patients might benefit from an internal jugular – transjugular – approach for transcatheter pulmonary valve implantation.
This multicentre retrospective study included all patients who underwent attempted transcatheter pulmonary valve placement in the right ventricular outflow tract between April 2010 and June 2012 at two large congenital heart centres. Patients were divided into two groups based on venous access site – transfemoral or transjugular. Patient characteristics, procedural outcomes, and complications were compared between groups.
Of 81 patients meeting the inclusion criteria (median age 16.4 years), the transjugular approach was used in 14 patients (17%). The transjugular group was younger (median age 11.9 versus 17.3 years), had lower body surface area (mean 1.33 versus 1.61 m2), more often had moderate or greater tricuspid regurgitation (29% versus 7%), and had a higher ratio of right ventricle-to-systemic systolic pressure (mean 82.4 versus 64.7). Patients requiring a transjugular approach after an unsuccessful transfemoral approach had longer fluoroscopic times and procedure duration.
The transjugular approach for transcatheter pulmonary valve implantation is used infrequently but is more often used in younger and smaller patients. Technical limitations from a transfemoral approach may be anticipated if there is moderate or greater tricuspid regurgitation or higher right ventricular pressures. In these patients, a transjugular approach should be considered early.
In traditional transit timing variations (TTVs) analysis of multi-planetary systems, the individual TTVs are first derived from transit fitting and later modelled using n-body dynamic simulations to constrain planetary masses. We show that fitting simultaneously the transit light curves with the system dynamics (photo-dynamical model) increases the precision of the TTV measurements and helps constrain the system architecture. We exemplify the advantages of applying this photo-dynamical model to a multi-planetary system found in K2 data very close to 3:2 mean motion resonance, K2-19. In this case the period of the larger TTV variations (libration period) is much longer (>1.5 years) than the duration of the K2 observations (80 days). However, our method allows to detect the short period TTVs produced by the orbital conjunctions between the planets that in turn permits to uniquely characterise the system. Therefore, our method can be used to constrain the masses of near-resonant systems even when the full libration curve is not observed.
Model alloys have been made of pure W and 1% & 5% W-Ta and W-Re. Indentation hardness and modulus data were obtained by nanoindentation to assess the effect of composition on mechanical properties. Results showed that both the Ta and Re compositions hardened with increasing alloy content, greater in the W-5%Ta composition which showed an increase of 1.03GPa (17%), compared to a 0.43GPa (7%) increase in W-5%Re. The samples also showed very small increases in modulus of ∼ 25GPa (6%) in both W-5%Re and W-5%Ta. The samples were implanted with 3000appm concentration of helium. All samples show a substantial increase in hardness of up to 107% in the case of pure W. An appreciable difference in modulus is also seen in all samples. Initial TEM work has shown no visible He bubbles, suggesting that the mechanical properties changes are due to He-vacancy cluster formation below the resolvable limit.
The electrodeposition of hydrated ruthenium dioxide (hRuO2) on Ti interdigitated current collectors deposited onto silicon substrate has been investigated with the objective of preparing a high capacitance and high power micro-supercapacitor (µ-SC) device. Ti current collectors were synthesised by typical photolithography processes, and hRuO2 thin films were electrodeposited from ruthenium chloride precursors. Device specific capacitances exceeding 20 mF·cm−2 were obtained, and more than 80 % of that value is retained even at scan rate as high as 1 V∙s−1 in 0.5 M H2SO4. The mean specific power per active surface area of the device is 368 mW·cm−2. The device is stable and 90% of the initial capacity is retained after 105 cycles (1 V potential window). The characteristic response time of the hRuO2 µ-SC is 250 ms, with low ESR (0.61 Ω cm−2) and EDR (0.07 Ω cm−2) values. All these characteristics demonstrate the potential of such µ-SC devices to be part of the next generation of micro-supercapacitors.
The effect of elevated carbon dioxide (CO2) concentration on greenhouse gas (GHG) emission from semi-arid cropping systems is poorly understood. Closed static chambers were used to measure the fluxes of nitrous oxide (N2O), CO2 and methane (CH4) from a spring wheat (Triticum aestivum L. cv. Yitpi) crop-soil system at the Australian grains free-air carbon dioxide enrichment (AGFACE) facility at Horsham in southern Australia in 2009. The targeted atmospheric CO2 concentrations (hereafter CO2 concentration is abbreviated as [CO2]) were 390 (ambient) and 550 (elevated) μmol/mol for both rainfed and supplementary irrigated treatments. Gas measurements were conducted at five key growth stages of wheat. Elevated [CO2] increased the emission of N2O and CO2 by 108 and 29%, respectively, with changes being greater during the wheat vegetative stage. Supplementary irrigation reduced N2O emission by 36%, suggesting that N2O was reduced to N2 in the denitrification process. Irrigation increased CO2 flux by 26% at ambient [CO2] but not at elevated [CO2], and had no impact on CH4 flux. The present results suggest that under future atmospheric [CO2], agricultural GHG emissions at the vegetative stage may be higher and irrigation is likely to reduce the emissions from semi-arid cropping systems.
Ionic and mixed conducting oxides (La0.9Sr0.1)[(Ga1-xFex)0.8Mg0.2]O3-y (I) and (Sr1.8La0.2)(GaFe)O5.1 (II) with the perovskite and brownmillerite structures, respectively, have been prepared in forms of dense bulk ceramics and ceramic coatings by the sol-gel method. Thin films II have been grown by the pulsed laser deposition method on single crystal MgO (100) and Si (100), fused silica, and stainless steel substrates. The films grown under optimal process conditions were single-phase and homogeneous, with a high degree of preferential orientation. The structure and microstructure of the ceramic coatings have been studied by X-ray diffraction and scanning electron microscopy.
In February and in June 1998, two people developed acute hepatitis B following in-patient care in a district general hospital. Initial enquiries indicated their infections were not attributable to staff undertaking exposure-prone procedures (EPPs). We report the findings and implications of the subsequent investigation: a multi-disciplinary, multi-agency investigation, including molecular epidemiological analysis. Occupational Health records showed that staff involved in EPPs with the patients were HBsAg negative. No contact between the patients was identified nor were there failures in sterilization. The patients' HBV strains were identical, indicating a common source. A total of 231 out of 232 staff who might have treated either patient were tested for HBsAg; the remaining doctor, working abroad, was HBsAg- and HBeAg-positive and had the same HBV strain as the patients. On two occasions the doctor's hand had been cut while breaking glass vials, but there was no documentation linking these events to the two patients. The doctor had been vaccinated in 1993 and tested for anti-HBs prior to commencing work in 1997. The doctor was recalled to Occupational Health but did not attend and was not followed up. In total, 4948 patients potentially treated by the doctor received an explanatory letter and 3150 were tested for HBsAg. Only one was positive, and HBV sequencing showed no link to the doctor. Occasionally transmission of HBV from heath-care workers can occur in a non-EPP setting and the implications of this require examination by those setting national policy. Occupational Health Services should investigate clinical heath-care workers who do not respond to vaccination. They should ensure HBV carriers are identified and offer them appropriate advice to prevent transmission to patients.
The upper part of cores of the Onakawana B Drillhole in the Moose River Basin in northern Ontario includes the upper part of the upper member of the Williams Island Formation (22.5 m, 16 samples), and the entire overlying Long Rapids Formation (75.1 m, 49 samples). The sequence of conodonts from the drillhole was analyzed by graphic correlation as well as conventional zonation.
The upper carbonate member of the Williams Island Formation correlates with lower Frasnian zones 2 to 5. Below this, mixed Frasnian and Famennian conodont faunas occur partly in a brecciated interval within the member and represent stratigraphic leak below the Frasnian. The lower member of the Long Rapids Formation correlates in its lowest part with Zone 5, followed by a hiatus of zones 6 to 8. This is succeeded by zones 9 and 10. Zone 11 is missing, followed by an interval that correlates with upper Frasnian zones 12 and 13 to within the lower Famennian Middle triangularis Zone. The Frasnian-Famennian boundary occurs within a narrow interval in the lower member. The Upper triangularis Zone and perhaps part of the Middle triangularis Zone are missing.
The middle member of the Long Rapids Formation correlates with the Lower to Uppermost crepida zones. A sequence from high in the rhomboidea Zone to within the Lower marginifera to perhaps slightly into the Upper marginifera Zone occurs in the upper member of the formation.
Sixteen species are described, of which seven are new: Palmatolepis angularis, P. angusta, P. mystica, P. nodosa, P. parva, Palmatolepis n. sp. A, and Mehlina? unica. Two species that affect definition and identification of the Frasnian-Famennian boundary, P. triangularis and P. ultima (=P. praetriangularis), are revised.
There is a need to identify finishing systems for pigs that meet the requirements of both pig producers and society. These require that a system is economically efficient, but also takes due account of animal welfare, food safety and environmental considerations. As part of an integrated investigation, this study assessed the health and welfare implications of giving pigs either dry or liquid feed when housed in either fully-slatted or straw-based accommodation.
The physical origin of the yellow luminescence in MBE-grown GaN co-doped with C and Si was investigated. Deep level optical spectroscopy (DLOS), deep level transient spectroscopy (DLTS), and photoluminescence (PL) were used to study the deep level spectrum as a function of C incorporation. In the absence of C co-doping, samples were n-type and demonstrated a weak yellow luminescence band, likely related to VGa. For increasing C co-doping, samples became semi-insulating concurrent with increased intensity of the yellow luminescence and the concentration of C-related deep acceptors. The DLOS results were used to develop a configuration-coordinate model for a C-related deep level with optical ionization energy of 3.0 eV and Franck-Condon shift of 0.4 eV that is consistent with the observed yellow luminescence and DLTS results. From these findings, a general model for independent mechanisms of the yellow luminescence related to VGa for n-type GaN and C for n-type and semi-insulating GaN:C:Si is discussed.
Zoonoses are those diseases of animals that can be transmitted to man or vice versa. These may be caused by bacteria, parasites, or more rarely by viruses. This paper will concentrate mainly on the zoonotic bacteria Salmonella spp., Campylobacter spp., E. coli O157 and Yersinia spp. Foodborne disease, often described as food poisoning, is defined as disease due to the consumption of food contaminated with microorganisms or their toxins. In 2000, the most common causes of food poisoning in humans in Great Britain were Campylobacter spp. (60340 cases) and Salmonella spp. (16567 cases). Less than 100 cases of Yersinia spp. infections were reported in humans in England and Wales. Results from surveillance of zoonotic organisms in farm livestock were presented at two conferences organised by MAFF in 2000. The main results are outlined in table 1. It is not possible to guarantee the complete absence from meat of bacteria that can cause infections in people. Thorough cooking of foods should kill all vegetative bacteria. Nevertheless, it is also important that steps are taken throughout the supply chain to minimise the transfer of the bacteria that could cause foodborne disease.
Between 1989 and 1993, 17 experiments tested the
effect of cover crop species, sowing date and
destruction date on cover crop dry matter (DM) yield, N
uptake and on soil mineral nitrogen (SMN)
content. All the experiments were carried out in Suffolk,
Norfolk, Lincolnshire and Yorkshire on
sandy-loam textured soils after crops of cereals or
oilseed rape had been harvested. The largest DM
yields were obtained with early sowings and averaged
1·6 t/ha. Cover crop N uptake was less
dependent upon sowing date and averaged 35 kg N/ha.
The average reduction in SMN was from 46
to 32 kg N/ha. Differences between cover crop species
were small when compared with season/site variations.
Cereal cover crop DM yields were closely related to the
thermal time accumulated from the first
significant rainfall after sowing, whilst the yields of
non-cereal cover crops were more affected by the
moisture content of the soil at sowing. The amount of
SMN in the soil at sowing had little or no effect
on cover crop yield. The yields of cereal cover crops were
much more predictable than those of non-cereal cover
crops. Water usage by cover crops was estimated to be
20 mm/t DM and large cover
crops delayed the onset of leaching and reduced the
amount of water leached. However, even in dry
autumns and winters, soils are likely to reach field
capacity before the following beet crop is sown.
Due to their large C[ratio ]N ratio (20[ratio ]1) little
N would be mineralized after cover crop destruction. Cover
crops comprising volunteer cereals and weeds often
performed as well as the other cover crops and
in most cases will be the most cost-effective cover crops.