Remediation of salt-affected soil by natural and chemical amendments to improve berseem clover yield and nutritive quality

Salinity is a major problem affecting crop production worldwide. The potential of different soil amendments (sulphur, gypsum, compost, and combination of gypsum, compost and sulphur) and two plant-growth stimulators (potassium silicate and calcium carbonate nanoparticles) to alleviate the harmful effects of saline soil on two cultivars of berseem clover (Trifolium alexandrinum L.), one salt tolerant (‘Serw-1’) and the other high yielding (‘Helaly’), was evaluated. Some soil properties were measured before and after treatments. Plant growth parameters, herbage yield, nutritive value and plant metabolites, including photosynthetic pigment and endogenous hormone contents, were also determined. The herbage yield of berseem clover cultivars substantially increased with the application of soil amendments in both years. The greatest yield increase was obtained with the compost application. The highest protein contents in herbage (16.4% in Helaly and 17.2% in Serw-1) were detected in response to composite (compost + gypsum + sulphur) and compost treatments, respectively. Carbohydrate content increased to 9.53% in Helaly and 5.1% in Serw-1 in response to the gypsum and compost treatments, respectively. The composite, compost and gypsum soil amendments were the most effective treatments resulting in the greatest herbage yield and quality values.Keywords: chemical composition, growth stimulators, salinity, soil amendments, Trifolium alexandrinum, yiel

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population