Nonequilibrium wetting

When a nonequilibrium growing interface in the presence of a wall is considered a nonequilibrium wetting transition may take place. This transition can be studied trough Langevin equations or discrete growth models. In the first case, the Kardar-Parisi-Zhang equation, which defines a very robust universality class for nonequilibrium moving interfaces, with a soft-wall potential is considered. While in the second, microscopic models, in the corresponding universality class, with evaporation and deposition of particles in the presence of hard-wall are studied. Equilibrium wetting is related to a particular case of the problem, it corresponds to the Edwards-Wilkinson equation with a potential in the continuum approach or to the fulfillment of detailed balance in the microscopic models. In this review we present the analytical and numerical methods used to investigate the problem and the very rich behavior that is observed with them.Comment: Review, 36 pages, 16 figure

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

The Potential Of Periphyton-based Cage Culture Of Nile Tilapia In A Brazilian Reservoir

In land-based pond cultures, periphyton is considered to be a complementary food source for cultured fish. In cage aquaculture, studies on the use of periphyton are scarce and do not support the viability of periphyton-based cage culture. The aim of this study was to evaluate the potential of periphyton-based cage culture of Nile tilapia in a hydroelectric reservoir in Brazil at three stocking densities and two feeding regimes. Sex-reversed male Nile tilapia Oreochromis niloticus (46.56 ± 2.53 g) were placed in 21 cages (6 m3 - 2 × 2 × 1.5 m each) with or without bamboo substrates for periphyton growth. A completely randomized design with three replicates per treatment was used to test the effect of substrate inclusion in the three stocking densities (80, 60, 40 kg of fish/m3) associated with two feeding regimes (100% and 50% of daily ration). Three cages without bamboo substrates were included in the experimental design as control group (CTRL) (80 kg/m3 and 100% of daily ration). The study demonstrates the efficiency of using substrates for Nile tilapia in cages in the reservoir. The presence of bamboo substrates improved the weight gain of fish but reduced the carrying capacity of the cage at the highest density. The concentration of dissolved oxygen in the cages was improved by the presence of substrate between 50 and 140 days of the trial and reduced after 155 days of culture. The inclusion of bamboo substrates inside the cages allows producing up to 52 kg/m3 of Nile tilapia using 32% less diet in a period almost 20% shorter than in the CTRL group. If farmers prefer to produce 80 kg/m3, they can use 30% less diet but the production period would be 20% longer. Statement of relevance: This study has high relevance to the general field of commercial aquaculture because the experiment was carried out at a commercial fish farm, under real environmental conditions and management. Presented results are promising because show that bamboo substrates in cages improve the efficiency of the system up to 52 kg/m3. This production model may be an efficient alternative for family farmers. © 2016 Elsevier B.V.46422923