Cropping diversity and input use affect weed competition

Non-Peer ReviewedOf the various pests affecting crop growth weeds are among the most visible and potentially the most damaging. Changing markets, higher input costs and technological change are having a profound impact on weed management decisions in Western Canada. While the decision to change management practices can be immediate the long term agronomic consequences of adopting a farm management system are not well understood. One objective of a long term study, established at Scott in 1995, was to investigate the impact of 3 levels of inputs and 3 levels of cropping diversity on in-crop weed competition. Weed biomass used as an indicator of weed competition, was found to be largely a function of input level decisions and the interaction of weed control operations with precipitation timing. Greater weed biomass in an Organic input system could be linked to a limited number of early season tillage operations occurring over a short window of opportunity near the time of seeding. Herbicides applied later in the growing season in the Reduced and High input system effectively delayed weed growth and reduced weed biomass. Weeds in the Organic input system tended to respond to June-July precipitation while weed growth in the Reduced and High input system increased as July precipitation increased. Differences between cropping diversities were less pronounced showing similar weed biomass trends over time

Body mass index and complications following major gastrointestinal surgery: A prospective, international cohort study and meta-analysis

Aim Previous studies reported conflicting evidence on the effects of obesity on outcomes after gastrointestinal surgery. The aims of this study were to explore the relationship of obesity with major postoperative complications in an international cohort and to present a metaanalysis of all available prospective data. Methods This prospective, multicentre study included adults undergoing both elective and emergency gastrointestinal resection, reversal of stoma or formation of stoma. The primary end-point was 30-day major complications (Clavien–Dindo Grades III–V). A systematic search was undertaken for studies assessing the relationship between obesity and major complications after gastrointestinal surgery. Individual patient meta-analysis was used to analyse pooled results. Results This study included 2519 patients across 127 centres, of whom 560 (22.2%) were obese. Unadjusted major complication rates were lower in obese vs normal weight patients (13.0% vs 16.2%, respectively), but this did not reach statistical significance (P = 0.863) on multivariate analysis for patients having surgery for either malignant or benign conditions. Individual patient meta-analysis demonstrated that obese patients undergoing surgery formalignancy were at increased risk of major complications (OR 2.10, 95% CI 1.49–2.96, P < 0.001), whereas obese patients undergoing surgery for benign indications were at decreased risk (OR 0.59, 95% CI 0.46–0.75, P < 0.001) compared to normal weight patients. Conclusions In our international data, obesity was not found to be associated with major complications following gastrointestinal surgery. Meta-analysis of available prospective data made a novel finding of obesity being associated with different outcomes depending on whether patients were undergoing surgery for benign or malignant disease