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The Single Ventricle Reconstruction Trial randomised neonates with hypoplastic left heart syndrome to a shunt strategy but otherwise retained standard of care. We aimed to describe centre-level practice variation at Fontan completion.
Centre-level data are reported as median or median frequency across all centres and range of medians or frequencies across centres. Classification and regression tree analysis assessed the association of centre-level factors with length of stay and percentage of patients with prolonged pleural effusion (>7 days).
The median Fontan age (14 centres, 320 patients) was 3.1 years (range from 1.7 to 3.9), and the weight-for-age z-score was −0.56 (−1.35 + 0.44). Extra-cardiac Fontans were performed in 79% (4–100%) of patients at the 13 centres performing this procedure; lateral tunnels were performed in 32% (3–100%) at the 11 centres performing it. Deep hypothermic circulatory arrest (nine centres) ranged from 6 to 100%. Major complications occurred in 17% (7–33%). The length of stay was 9.5 days (9–12); 15% (6–33%) had prolonged pleural effusion. Centres with fewer patients (<6%) with prolonged pleural effusion and fewer (<41%) complications had a shorter length of stay (<10 days; sensitivity 1.0; specificity 0.71; area under the curve 0.96). Avoiding deep hypothermic circulatory arrest and higher weight-for-age z-score were associated with a lower percentage of patients with prolonged effusions (<9.5%; sensitivity 1.0; specificity = 0.86; area under the curve 0.98).
Fontan perioperative practices varied widely among study centres. Strategies to decrease the duration of pleural effusion and minimise complications may decrease the length of stay. Further research regarding deep hypothermic circulatory arrest is needed to understand its association with prolonged pleural effusion.
Schmidt-hammer exposure-age dating (SHD) of boulders on cryoplanation terrace treads and associated bedrock cliff faces revealed Holocene ages ranging from 0 ± 825 to 8890 ± 1185 yr. The cliffs were significantly younger than the inner treads, which tended to be younger than the outer treads. Radiocarbon dates from the regolith of 3854 to 4821 cal yr BP (2σ range) indicated maximum rates of cliff recession of ~0.1 mm/yr, which suggests the onset of terrace formation before the last glacial maximum. Age, angularity, and size of clasts, together with planation across bedrock structures and the seepage of groundwater from the cliff foot, all support a process-based conceptual model of cryoplanation terrace development in which frost weathering leads to parallel cliff recession and, hence, terrace extension. The availability of groundwater during autumn freezeback is viewed as critical for frost wedging and/or the growth of segregation ice during prolonged winter frost penetration. Permafrost promotes cryoplanation by providing an impermeable frost table beneath the active layer, focusing groundwater flow, and supplying water for sediment transport by solifluction across the tread. Snow beds are considered an effect rather than a cause of cryoplanation terraces, and cryoplanation is seen as distinct from nivation.
The objective of this study was to investigate the impact of the most commonly cited factors that may have influenced infants’ gut microbiota profiles at one year of age: mode of delivery, breastfeeding duration and antibiotic exposure. Barcoded V3/V4 amplicons of bacterial 16S-rRNA gene were prepared from the stool samples of 52 healthy 1-year-old Australian children and sequenced using the Illumina MiSeq platform. Following the quality checks, the data were processed using the Quantitative Insights Into Microbial Ecology pipeline and analysed using the Calypso package for microbiome data analysis. The stool microbiota profiles of children still breastfed were significantly different from that of children weaned earlier (P<0.05), independent of the age of solid food introduction. Among children still breastfed, Veillonella spp. abundance was higher. Children no longer breastfed possessed a more ‘mature’ microbiota, with notable increases of Firmicutes. The microbiota profiles of the children could not be differentiated by delivery mode or antibiotic exposure. Further analysis based on children’s feeding patterns found children who were breastfed alongside solid food had significantly different microbiota profiles compared to that of children who were receiving both breastmilk and formula milk alongside solid food. This study provided evidence that breastfeeding continues to influence gut microbial community even at late infancy when these children are also consuming table foods. At this age, any impacts from mode of delivery or antibiotic exposure did not appear to be discernible imprints on the microbial community profiles of these healthy children.
Terrestrial gastropods are problematical for radiocarbon (14C) measurement because they tend to incorporate carbon from ancient sources as a result of their dietary behavior. The 14C ecology of the pulmonate land snail, Helix melanostoma in Cyrenaica, northeastern Libya, was investigated as part of a wider study on the potential of using terrestrial mollusk shell for 14C dating of archaeological deposits. H. melanostoma was selected out of the species available in the region as it has the most predictable 14C ecology and also had a ubiquitous presence within the local archaeology. The ecological observations indicate that H. melanostoma has a very homogenous 14C ecology with consistent variations in F14C across sample sites controlled by availability of dietary vegetation. The majority of dated specimens from non-urbanized sample locations have only a small old-carbon effect, weighted mean of 476±48 14C yr, with between ~1% and 9% of dietary F14C from non-organic carbonate sources. Observed instabilities in the 14C ecology can all be attributed to the results of intense human activity not present before the Roman Period. Therefore, H. melanostoma and species with similar ecological behavior are suitable for 14C dating of archaeological and geological deposits with the use of a suitable offset.
A survey of the Milky Way disk and the Magellanic System at the wavelengths of the 21-cm atomic hydrogen (H i) line and three 18-cm lines of the OH molecule will be carried out with the Australian Square Kilometre Array Pathfinder telescope. The survey will study the distribution of H i emission and absorption with unprecedented angular and velocity resolution, as well as molecular line thermal emission, absorption, and maser lines. The area to be covered includes the Galactic plane (|b| < 10°) at all declinations south of δ = +40°, spanning longitudes 167° through 360°to 79° at b = 0°, plus the entire area of the Magellanic Stream and Clouds, a total of 13 020 deg2. The brightness temperature sensitivity will be very good, typically σT≃ 1 K at resolution 30 arcsec and 1 km s−1. The survey has a wide spectrum of scientific goals, from studies of galaxy evolution to star formation, with particular contributions to understanding stellar wind kinematics, the thermal phases of the interstellar medium, the interaction between gas in the disk and halo, and the dynamical and thermal states of gas at various positions along the Magellanic Stream.
A heuristic greedy algorithm is developed for efficiently tiling spatially dense redshift surveys. In its first application to the Galaxy and MassAssembly (GAMA) redshift survey we find it rapidly improves the spatial uniformity of our data, and naturally corrects for any spatial bias introduced by the 2dF multi-object spectrograph. We make conservative predictions for the final state of the GAMA redshift survey after our final allocation of time, and can be confident that even if worse than typical weather affects our observations, all of our main survey requirements will be met.
Field studies were conducted to compare the effectiveness of PRE and POST applications of a prepackaged mixture of flufenacet plus metribuzin with that of diclofop for winter wheat tolerance and control of Italian ryegrass. Additional studies investigated the effectiveness of reduced rates of flufenacet plus metribuzin applied POST to Italian ryegrass when wheat was in the spike stage. All PRE and POST applications of flufenacet plus metribuzin produced similar or greater injury to wheat and more consistent control of Italian ryegrass than PRE or POST applications of diclofop. PRE applications of flufenacet plus metribuzin controlled Italian ryegrass 73 to 77%, whereas POST applications controlled Italian ryegrass 77 to 99%. PRE applications of diclofop controlled Italian ryegrass 57%; POST application controlled Italian ryegrass 78%. Wheat injury from flufenacet plus metribuzin applications varied with application rate, cultivar, and year of application.
There is increasing epidemiological evidence linking sub-optimal vitamin D status with overweight and obesity. Although increasing BMI and adiposity have also been negatively associated with the change in vitamin D status following supplementation, results have been equivocal. The aim of this randomised, placebo-controlled study was to investigate the associations between anthropometric measures of adiposity and the wintertime serum 25-hydroxycholecalciferol (25(OH)D) response to 15 μg cholecalciferol per d in healthy young and older Irish adults. A total of 110 young adults (20–40 years) and 102 older adults ( ≥ 64 years) completed the 22-week intervention with >85 % compliance. The change in 25(OH)D from baseline was calculated. Anthropometric measures of adiposity taken at baseline included height, weight and waist circumference (WC), along with skinfold thickness measurements to estimate fat mass (FM). FM was subsequently expressed as FM (kg), FM (%), FM index (FMI (FM kg/height m2)) and as a percentage ratio to fat-free mass (FFM). In older adults, vitamin D status was inversely associated with BMI (kg/m2), WC (cm), FM (kg and %), FMI (kg/m2) and FM:FFM (%) at baseline (r − 0·33, − 0·36, − 0·33, − 0·30, − 0·33 and − 0·27, respectively, all P values < 0·01). BMI in older adults was also negatively associated with the change in 25(OH)D following supplementation (β − 1·27, CI − 2·37, − 0·16, P = 0·026); however, no such associations were apparent in younger adults. Results suggest that adiposity may need to be taken into account when determining an adequate wintertime dietary vitamin D intake for healthy older adults residing at higher latitudes.
Octogenarians were excluded from participation in many carotid endarterectomy trials due to the high complication rates observed in past studies. However, stroke resulting from carotid stenosis is expected to increase with the aging population. Moreover, advances in Carotid Angioplasty and Stenting (CAS) techniques have resulted in perceived improved safety of this procedure. We sought to review our experience with carotid stenting in symptomatic octogenarians with an emphasis on short-term outcomes and complications.
This is a retrospective longitudinal cohort study of all symptomatic patients who underwent CAS in our center between 1997 and 2007. Thirty-day stroke and death rates, and length of hospitalization were compared between the symptomatic octogenarians and non-octogenarians.
A total of 214 procedures were performed on 211 symptomatic patients (56 females). Fifty-nine patients (14 females) were octogenarians. The median (interquartile range) age on procedure date for the octogenarian cohort was 83 (4) years. Periprocedural death occurred in two (3.4%) octogenarians and five (3.3%) non-octogenarians (p = 0.97). At 30 days from the procedure, stroke occurred in four (6.8%) octogenarians and seven (4.6%) non-octogenarians (p= 0.52). The mean hospital stay (4.8 days) was not different between the two cohorts. Age was not a predictor of the 30-day risk of composite stroke or death.
The complications rate observed in octogenarians was not significantly higher than non-octogenarians. Our findings suggest that octogenarians should be included in randomized trials examining CAS to better define the risk-benefit profile of this procedure in the elderly.
Although carotid endarterectomy is considered the ‘gold standard’ for standard risk symptomatic patients, the treatment of choice for asymptomatic patients remains controversial. Carotid stenting has demonstrated real-world outcomes consistent with established guidelines for carotid endarterectomy in asymptomatic high-surgical risk patients in recent prospective multicenter trials. We describe our experience with asymptomatic patients who underwent carotid stenting at our center in a routine clinical setting.
This is a retrospective, longitudinal cohort study of patients who underwent carotid angioplasty and stenting at the Foothills Medical Center, Calgary, Canada between 1997 and 2007. The qualifying events were categorized as symptomatic and asymptomatic. The procedures were performed by four experienced neurointerventionists. The primary outcome was stroke or death at 30-day follow- up.
243 patients underwent 255 carotid stenting procedures. Their ages ranged from 50 to 83 years; the mean age was 72.0 ± 9.3 years; 67(26.3%) were women. Forty one patients (16.1%) were asymptomatic; 214 patients (83.9%) were symptomatic. The patients in the asymptomatic group were significantly younger - 66.0 ± 8.8 years compared to patients in the symptomatic group 73.2 ± 8.9 years (p<0.0001). Intraprocedurally one minor stroke (2.4%) occurred in the asymptomatic group. At 30-day follow-up, no deaths or further strokes were noted in the asymptomatic group; while eight deaths, six major and seven minor strokes occurred in the symptomatic group (p=0.22).
Carotid stenting appears to be a safe procedure in asymptomatic patients with severe carotid stenosis in routine clinical settings as witnessed in this single center study.