Selective digestive or oropharyngeal decontamination and topical oropharyngeal chlorhexidine for prevention of death in general intensive care : systematic review and network meta-analysis

Peer reviewedPublisher PD

California Community Choice Aggregation Law & Regulation

The purpose of this special topic is to provide a summary of the laws and regulations associated with the development of Community Choice Aggregation (“CCA”) in California and the growing impact of CCA in the California energy market

Toward Magnetic Resonance Only Treatment Planning: Distortion Mitigation And Image-Guided Radiation Therapy Validation

While MR-only treatment planning has shown promise, there are still several well-known challenges that are currently limiting widespread clinical implementation. Firstly, MR images are affected by both patient-induced and system-level geometric distortions that can significantly degrade treatment planning accuracy. . In addition, the availability of comprehensive distortion analysis software is currently limited. Also while many groups have been working toward a synthetic CT solution, further study is needed on the implementation of synCTs as the reference datasets for linac-based image-guided radiation therapy (IGRT) to help determine their robustness in an MR-only workflow. A 36×43×2 cm3 phantom with 255 known landmarks (~1 mm3) was scanned using 1.0T high-field open MR-SIM at isocenter in the transverse, sagittal, and coronal axes, and a 465x350x168mm 3D phantom was scanned by stepping in the superior-inferior direction in 3 overlapping positions to achieve a total 465x350x400mm sampled FOV yielding \u3e13,800 landmarks(3D Gradient-Echo, TE/TR/α = 5.54 ms/30 ms/28°, voxel size =1×1×2mm3). A binary template (reference) was generated from a phantom schematic. An automated program converted MR images to binary via masking, thresholding, and testing for connectivity to identify landmarks. Distortion maps were generated by centroid mapping. Images were corrected via warping with inverse distortion maps, and temporal stability was assessed. To determine candidate materials for phantom and software development, 1.0 T MR and CT images were acquired of twelve urethane foam samples of various densities and strengths. Samples were precision machined to accommodate 6 mm diameter paintballs used as landmarks. Final material candidates were selected by balancing strength, machinability, weight, and cost. Bore sizes and minimum aperture width resulting from couch position were tabulated from the literature (14 systems, 5 vendors). Bore geometry and couch position were simulated using MATLAB to generate machine-specific models to optimize the phantom build. Previously developed software for distortion characterization was modified for several magnet geometries (1.0 T, 1.5 T, 3.0 T), compared against previously published 1.0 T results, and integrated into the 3DSlicer application platform. To evaluate the performance of synthetic CTs in an image guided workflow, magnetic resonance simulation and CT simulation images were acquired of an anthropomorphic skull phantom and 12 patient brain cancer cases. SynCTs were generated using fluid attenuation inversion recovery, ultrashort echo time, and Dixon data sets through a voxel-based weighted summation of 5 tissue classifications. The DRRs were generated from the phantom synCT, and geometric fidelity was assessed relative to CT-generated DRRs through bounding box and landmark analysis. An offline retrospective analysis was conducted to register cone beam CTs to synCTs and CTs using automated rigid registration in the treatment planning system. Planar MV and KV images were rigidly registered to synCT and CT DRRs using an in-house script. Planar and volumetric registration reproducibility was assessed and margin differences were characterized by the van Herk formalism. Over the sampled FOV, non-negligible residual gradient distortions existed as close as 9.5 cm from isocenter, with a maximum distortion of 7.4mm as close as 23 cm from isocenter. Over 6 months, average gradient distortions were -0.07±1.10 mm and 0.10±1.10 mm in the x and y-directions for the transverse plane, 0.03±0.64 and -0.09±0.70 mm in the sagittal plane, and 0.4±1.16 and 0.04±0.40 mm in the coronal plane. After implementing 3D correction maps, distortions were reduced to \u3c 1 pixel width (1mm) for all voxels up to 25 cm from magnet isocenter. All foam samples provided sufficient MR image contrast with paintball landmarks. Urethane foam (compressive strength ∼1000psi, density ~20lb/ft3) was selected for its accurate machinability and weight characteristics. For smaller bores, a phantom version with the following parameters was used: 15 foam plates, 55×55×37.5 cm3 (L×W×H), 5,082 landmarks, and weight ~30 kg. To accommodate \u3e70 cm wide bores, an extended build used 20 plates spanning 55×55×50 cm3 with 7,497 landmarks and weight ~44 kg. Distortion characterization software was implemented as an external module into 3DSlicer’s plugin framework and results agreed with the literature. Bounding box and landmark analysis of phantom synCT DRRs were within 1 mm of CT DRRs. Absolute planar registration shift differences ranged from 0.0 to 0.7 mm for phantom DRRs on all treatment platforms and from 0.0 to 0.4 mm for volumetric registrations. For patient planar registrations, the mean shift differences were 0.4±0.5 mm (range, 0.6 to 1.6 mm), 0.0±0.5 mm (range, 0.9 to 1.2 mm), and 0.1±0.3 mm (range, 0.7 to 0.6 mm) for the superior-inferior (S-I), left-right (L-R), and anterior-posterior (A-P) axes, respectively. The mean shift differences in volumetric registrations were 0.6±0.4 mm (range, 0.2 to 1.6 mm), 0.2±0.4 mm (range, 0.3 to 1.2 mm), and 0.2±0.3 mm (range, 0.2 to 1.2 mm) for the S-I, L-R, and A-P axes, respectively. The CT-SIM and synCT derived margins were \u3c0.3mm different. This work has characterized the inaccuracies related to GNL distortion for a previously uncharacterized MR-SIM system at large FOVs, and established that while distortions are still non-negligible after current vendor corrections are applied, simple post-processing methods can be used to further reduce these distortions to less than 1mm for the entire field of view. Additionally, it was important to not only establish effective corrections, but to establish the previously uncharacterized temporal stability of these corrections. This work also developed methods to improve the accessibility of these distortion characterizations and corrections. We first tested the application of a more readily available 2D phantom as a surrogate for 3D distortion characterization by stepping the table with an integrated batch script file. Later we developed and constructed a large modular distortion phantom using easily obtainable materials, and showed and constructed a large modular distortion phantom using easily obtainable materials, and used it to characterize the distortion on several widely available MR systems. To accompany this phantom, open source software was also developed for easy characterization of system-dependent distortions. Finally, while the dosimetric equivalence of synCT with CT has been well established, it was necessary to characterize any differences that may exist between synCT and CT in an IGRT setting. This work has helped to establish the geometric equivalence of these two modalities, with some caveats that have been discussed at length

Effects of Various Growth Regulants on the Growth and Quality of Three Turf-Type Bermudagrasses

Agronom

NONLINEAR ESTIMATION OF GROWTH CURVE MODELS FOR GERMINATION DATA ANALYSIS

Logistic, Gompertz, Richards and Weibull growth curves were evaluated for their suitability as mathematical and empirical models to represent cumulative germination. By avoiding the limitations associated with the method of moments and single-value germination indices, the fitted models provided superior description of the time course of germination. The four-parameter Weibull model gave the best fit across a relatively wide range of seed species and germination conditions, and the resulting parameter estimates reflected identifiable aspects of the germination process. The nonlinear estimation of the germination response included a parameter summary, together with their asymptotic standard errors and correlation matrix, along with an approximate band for the expectation function, pairwise plots of the parameter inference region, and profile t plots. Evaluation of the fitted models also included information on lack of fit and residual structure. Empirical results and hypothesis testing were demonstrated with reference to a replicated experiment designed to determine the effects of reduced water potential on germination of onion seeds

Resourcing and recognition: Academics\u27 perceptions of challenges experienced embedding work-integrated learning in the curriculum

This paper explores academics\u27 perceptions of work-integrated learning (WIL) resourcing provisions and challenges at one institution to better envisage institutional support for WIL. The study draws on the WIL Curriculum Classification Framework to unpack how support and resourcing aligns to different modes of WIL. This study reports on the perceptions of 95 academics from a range of disciplines, teaching a variety of WIL activities. Findings are organized under core resourcing challenges: workload and recognition; developing WIL; administering and scaling WIL; sustainable management of industry relationships, and; other support requirements. Findings suggest mixed perceptions on WIL resourcing, space for more WIL integration in subjects, and consensus on the under-recognition of WIL work. Findings highlight the invisibility of academics\u27 efforts to embed WIL in curriculum, showing clashes in workload modelling and WIL practices. The study has implications for institutional WIL resourcing and recommends more coherent policies for recognition of WIL work

A novel technique for reducing soil fertility in ecological restoration projects

Surface soil eutrophication hinders ecological restoration projects by favouring communities of low biodiversity. This study assesses the effectiveness of a novel technique known as topsoil inversion that may promote recovery from eutrophication. Topsoil inversion is undertaken by a deep plough, which buries 30 cm of topsoil under approximately 40 cm of subsoil. The main study site is within new community woodland on former agricultural land. It comprises deep ploughed and conventionally ploughed plots, to compare two planting types: wildflowers only, and wildflowers with trees. This presentation will discuss some preliminary findings of the effect of topsoil inversion on soil properties and plant tissue nutrient content. Surface soil fertility is lowered following inversion treatment, and this appears to affect plant nutrient sequestration. These results suggest that topsoil inversion has the potential to facilitate ecological restoration on eutrophic soil. This technique may have benefits for restoration projects taking place in a variety of habitats affected by air pollution, including former agricultural land and lowland heaths

"Appearance potent"? A content analysis of UK gay and straight men's magazines.

With little actual appraisal, a more 'appearance potent' (i.e., a reverence for appearance ideals) subculture has been used to explain gay men's greater body dissatisfaction in comparison to straight men's. This study sought to assess the respective appearance potency of each subculture by a content analysis of 32 issues of the most read gay (Attitude, Gay Times) and straight men's magazines (Men's Health, FHM) in the UK. Images of men and women were coded for their physical characteristics, objectification and nudity, as were the number of appearance adverts and articles. The gay men's magazines featured more images of men that were appearance ideal, nude and sexualized than the straight men's magazines. The converse was true for the images of women and appearance adverts. Although more research is needed to understand the effect of this content on the viewer, the findings are consistent with a more appearance potent gay male subculture

Detection of a glitch in the pulsar J1709-4429

We report the detection of a glitch event in the pulsar J1709$-$4429 (also known as B1706$-$44) during regular monitoring observations with the Molonglo Observatory Synthesis Telescope (UTMOST). The glitch was found during timing operations, in which we regularly observe over 400 pulsars with up to daily cadence, while commensally searching for Rotating Radio Transients, pulsars, and FRBs. With a fractional size of $\Delta\nu/\nu \approx 52.4 \times10^{-9}$, the glitch reported here is by far the smallest known for this pulsar, attesting to the efficacy of glitch searches with high cadence using UTMOST.Comment: 3 pages, 1 figur

The manipulation of midsole properties to alter impact characteristics in walking

The midsole of footwear can provide an opportunity to attenuate the impact at the foot-ground interface. The present study was undertaken to quantify impact in walking in different footwear midsoles, comparing footwear thickness and hardness variations. Methods: Footbed thickness (28-41 mm) and hardness (30-55 Shore A) were varied independently in 7 flip-flops. Thirteen subjects walked in the footwear variations on a level walkway in the gait laboratory as lower limb kinematics, vertical ground reaction force and peak positive axial tibial acceleration were quantified. Peak magnitude and time of the acceleration were quantified and the heel-strike transient was characterised for comparison between conditions with a repeated-measures ANOVA. Thickness and hardness variations were also compared using a drop-test protocol to replicate walking. Results: Lower limb joint angles did not vary at heel-strike, however, a faster vertical heel-velocity was recorded in the softer midsoles (e.g. 55 Shore A = -0.294±0.055, 30 Shore A= -0.328±0.052, p<.001). Varying the hardness of the midsoles also significantly altered tibial acceleration and force variables, however limited significant differences existed between the thickness variations in walking. Increasing the hardness of the heel section of the footwear increased the peak positive axial tibial acceleration values, for example increasing Shore A from 30 to 40 resulted in a 35% increase in this variable. Concurrently, the occurrence of heel-strike transients increased from 5.8% in the 30 Shore A condition to 22.5%, 46.7% and 71.7% of all trials in the 40, 47 and 55 Shore A conditions respectively. The drop-test protocol replicated the differences evident in the walking protocol despite magnitudes being elevated. Conclusion: Modifying midsole properties of flip-flop footwear, particularly hardness, alters the gait kinematics and the shock experienced by the wearer in walking. This may pose benefits in terms of comfort and reduction in loading to the lower limb, however the influence on foot motion at initial contact and footwear longevity should be further quantified