As the production of single use plastic packaging materials is increasing rapidly, the resultant generation of waste material is quickly becoming one of the world’s major environmental issues. These ...plastic materials are highly stable, with excellent material properties which can allow them to be used beyond their intended single use. To effectively utilize these recovered plastic materials, an understanding of their mechanical properties is required. The aim of this study was to assess the mechanical properties of recovered plastic bottles to prove the feasibility of utilisation for additional uses in non-shredding based recycling systems with lower energy requirements. This system would conserve the physical integrity of the bottles, using them as a raw material for new direct reuse and repurposing applications. Tensile tests were conducted on samples cut from polyethylene terephthalate (PET) bottles considering different sets of variables: cutting method, orientation of the samples and degradation method. The results clearly demonstrate the superior strength characteristics, and minimal effect of degradation, showing the potential for a whole new field of applications where these recovered materials could be used. However, successful adoption of this new concept relies on structural changes to the operations of recycling and manufacturing companies as well as legislators, regulators and the general public.
Agriculture is responsible for 98% of atmospheric ammonia (NH3) in Ireland, of which pigs and poultry produce 7%; with laying hens specifically contributing 0.6%. Though a small proportion of the ...national NH3 total emissions, the ecological impacts on sensitive sites attributed to laying hen farms can be substantial. NH3 emission monitoring was conducted in Spring (February to March) and Summer (July to August) 2016 to account for seasonal variation. The total average emission and ventilation rate was 0.25 g bird−1 day−1 and 931 cm3 s−1 bird−1. This is lower than the previously used emission factor for the Irish national inventory of 0.5 g bird−1 day−1, but broadly similar to factors reported in the United Kingdom (UK) and the European Union (EU). Dispersion modelling using monitored data indicated potentially acute effects within 84 m, critical level exceedance within 312 m and exceedance of 0.3 kg N ha−1 year−1 deposition within 2.9–5.2 km. The sensitivity of the model was tested using SCAIL-Agriculture emission and ventilation rates which showed P-values for one tailed critical level below 0.01 for all models, indicating that when normalised the maximum extents modelled by AERMOD were significantly different. This analysis showed emission rate having more influence than ventilation rate. Both parameters combined had the greatest increase in dispersion extent, on average 55.8% greater than the use of monitored rates. A deposition rate of 0.3 kg N ha−1 year−1 was modelled to occur within 5.1–7.7 km when using SCAIL-Agriculture rates. Indicating that the use of SCAIL-Agriculture recommended emission and ventilation rates would have been sufficiently precautionary to assess negative ecological effects on a Natura 2000 site under the Habitats Directive (92/43/EEC). In relation to Appropriate Assessment (AA) screening, the use of any contribution from a source within a set distance may be an appropriate full AA trigger.
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•Monitored average NH3 emission rate of 0.25 g bird−1 day−1.•Monitored average ventilation rate of 931 cm3 s−1 bird−1.•Potential critical level exceedance within 312 m of farm border from source alone.•0.3 kg N ha−1 year−1 exceeded within 2.9–5.2 km of farm border from source alone.•Modelled dispersion using SCAIL-Agriculture rates was 55.8% greater than monitored.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The intensification of agricultural production systems to produce food for the growing world population is envisaged to result in the increase in nitrous oxide emissions (N2O). The goal of this study ...was therefore to assess the effect of different management practices on greenhouse gas (GHG) emissions from contrasting grass-based suckler beef farms with a particular focus on N2O emissions. The contrasting grass-based suckler beef systems evaluated were intensive (INT) and extensive (EXT) steer and heifer (SH) beef systems and bull and heifer (BH) systems. A whole farm model approach was taken to simulate GHG emissions from these baseline systems using data from a long-term research trial and a hybrid economic-GHG model. Several aspects of the hybrid model were updated. Default values for nitrogen (N) content of fresh and conserved grass were replaced with prediction equations. N excretion and partitioning prediction equations and emission factors (EF) for N2O from grazing cattle and fertiliser were also updated. The four baseline systems were simulated to harvest first cut silage on May 24. The pasture fertiliser rate for the EXT and INT systems were 77 kg N ha−1 and 205 kg N ha−1, respectively. To test the effect of changing management practices, the four baseline systems were simulated at earlier (May 5) and later (June 28) first cut silage harvest dates and 50% higher and lower pasture fertiliser application rates. In total, GHG emissions from four baseline systems and sixteen alternative scenarios were simulated. The carbon footprint of the baseline systems in kg CO2-equivalent (CO2e) per kg of carcass weight (kg CO2e CW−1) ranged from 17.7 for BH EXT to 19.4 for SH INT. This was lower than the latest published EU average of 22.2 kg CO2e CW−1. Across all scenarios, the increase in fertiliser application rate and earlier first cut silage harvest date increased the kg N2O kg CW−1 of the four production systems. Due to younger slaughter age facilitating higher stocking rates and thus higher productivity per hectare, systems finishing males as bulls at 16 months had lower N2O and total GHG emissions than production systems finishing males as steers at 24 months. Therefore, BH EXT with increased fertiliser application rate and earlier silage harvest date was the most sustainable suckler to beef production system while SH EXT with reduced fertiliser application rate and later silage harvest date was the least sustainable suckler to beef production system due to longer time to slaughter and consequently lower stocking rate.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background:
The diagnosis of pneumonia has been hampered by a reliance on bacterial cultures which take several days to return a result, and are frequently negative. In critically ill patients this ...leads to the use of empiric, broad-spectrum antimicrobials and compromises good antimicrobial stewardship. The objective of this study was
to
establish the performance of a syndromic molecular diagnostic approach, using a custom TaqMan array card (TAC) covering 52 respiratory pathogens, and assess its impact on antimicrobial prescribing.
Methods:
The TAC was validated against a retrospective multi-centre cohort of broncho-alveolar lavage samples. The TAC was assessed prospectively in patients undergoing investigation for suspected pneumonia, with a comparator cohort formed of patients investigated when the TAC laboratory team were unavailable.
Co-primary outcomes were sensitivity compared to conventional microbiology and, for the prospective study, time to result. Metagenomic sequencing was performed to validate findings in prospective samples. Antibiotic free days (AFD) were compared between the study cohort and comparator group.
Results:
128 stored samples were tested, with sensitivity of 97% (95% confidence interval (CI) 88-100%). Prospectively, 95 patients were tested by TAC, with 71 forming the comparator group. TAC returned results 51 hours (interquartile range 41-69 hours) faster than culture and with sensitivity of 92% (95% CI 83-98%) compared to conventional microbiology. 94% of organisms identified by sequencing were detected by TAC. There was a significant difference in the distribution of AFDs with more AFDs in the TAC group (p=0.02). TAC group were more likely to experience antimicrobial de-escalation (odds ratio 2.9 (95%1.5-5.5)).
Conclusions:
Implementation of a syndromic molecular diagnostic approach to pneumonia led to faster results, with high sensitivity and impact on antibiotic prescribing.
Nutrient-rich antioxidant ingredients were produced from tomato fruit wastes using a microwave-assisted extraction (MAE) process. Different conditions of extraction time (t), temperature (T), ethanol ...concentration (Et) and solid/liquid ratio (S/L) were combined in a circumscribed central composite design and optimized by response surface methodology. The model was statistically validated and used for prediction in the experimental range. Under the global optimal MAE conditions (t=20min, T=180°C, Et=47.4% and S/L=45g/L), it was possible to obtain an extraction yield of 75.5% and ingredients with high levels of sugars, proteins, phenolics, and flavonoids, and interesting antioxidant properties measured via ABTS+ scavenging activity and oxidative haemolysis inhibition assay (OxHLIA). The antioxidant capacity of the extracts was lower compared to the one of commercial food additives. However, the sustainably developed ingredients may be used in the fortification and functionalisation of food, as well as for incorporation in feed products.
This study addresses current needs of the agri-food sector, namely the recycling of plant wastes and production of valuable extracts for the food/feed industry. A MAE process was developed and optimized to maximize the recovery of nutrients and antioxidants from tomato fruit wastes. The optimum processing conditions established in this study allowed a high extraction yield and reduced solvent consumption. MAE can be considered as a sustainable alternative to conventional extraction methods. These findings will contribute to promote a more sustainable bioeconomy in the agro-food sector.
•A circumscribed central composite design was employed to produce extracts of interest.•Response surface methodology was used to optimize the processing conditions.•Extracts with high levels of sugars, proteins, phenolics and flavonoids were obtained.•Extracts exhibit a high antioxidant capacity (measured via ABTS and OxHLIA assays).•The developed extracts had potential as fortifying and functionalizing agents for foods.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Caribbean Acropora spp. corals have undergone a decline in cover since the second half of the twentieth century. Loss of these architecturally complex and fast-growing corals has resulted in ...significant, cascading changes to the character, diversity, and available eco-spaces of Caribbean reefs. Few thriving Acropora spp. populations exist today in the Caribbean and western North Atlantic seas, and our limited ability to access data from reefs assessed via long-term monitoring efforts means that reef scientists are challenged to determine resilience and longevity of existing Acropora spp. reefs. Here we used multiple dating methods to measure reef longevity and determine whether Coral Gardens Reef, Belize, is a refuge for Acropora cervicornis against the backdrop of wider Caribbean decline. We used a new genetic-aging technique to identify sample sites, and radiocarbon and high-precision uranium-thorium (U-Th) dating techniques to test whether one of the largest populations of extant A. cervicornis in the western Caribbean is newly established after the 1980s, or represents a longer-lived, stable population. We did so with respect for ethical sampling of a threatened species. Our data show corals ranging in age from 1910 (14C) or 1915 (230Th) to at least November 2019. While we cannot exclude the possibility of short gaps in the residence of A. cervicornis earlier in the record, the data show consistent and sustained living coral throughout the 1980s and up to at least 2019. We suggest that Coral Gardens has served as a refuge for A. cervicornis and that identifying other, similar sites may be critical to efforts to grow, preserve, conserve, and seed besieged Caribbean reefs.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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