17 research outputs found
State of the worldâs plants and fungi 2020
Kewâs State of the Worldâs Plants and Fungi project provides assessments of our current knowledge of the diversity of plants and fungi on Earth, the global threats that they face, and the policies to safeguard them. Produced in conjunction with an international scientific symposium, Kewâs State of the Worldâs Plants and Fungi sets an important international standard from which we can annually track trends in the global status of plant and fungal diversity
Evidence for bias in C and N concentrations and ÎŽ13C composition of terrestrial and aquatic organic materials due to pre-analysis acid preparation methods
This study is the first systematic comparison of the effect of acid treatment methods on the reliability of organic carbon [C] and nitrogen [N], and carbon isotope (Ύ 13C) values on a range of terrestrial and aquatic, modern and geological environmental materials. We investigated the 3 most common methods; (i) acidification followed by sequential deionised water rinses ("rinse method"); (ii) acidification in silver capsules ("capsule method"); and (iii) acidification by exposure to an acid vapour ("fumigation method"). We also investigated the effect of sample size and capsule type (silver and tin) on C/N ratio and Ύ 13C values. We find (i) that %C, %N, C/N and Ύ 13C showed significant within and between method variability; (ii) disproportionate and non-linear offsets of %C, %N and C/N values after acidification within and between methods and within and between sample materials; (iii) that alterations in %C did not necessarily manifest themselves in shifts in Ύ 13C, and vice-versa; (iv) that small (~90-gC) sample sizes showed consistent overestimations and inaccuracies after acidification; (v) that the effect of capsule type was not significant on most samples, but did show a notable effect on our aquatic materials, generally increasing %C and %N, and producing depleted Ύ 13C values. These findings raise cause for concern on the interpretative nature of C/N ratios and their support for carbon isotope values. The comparability between laboratories (different preparation methods) and environmental settings (amount, type and nature of OM) is also likely to be problematic. We conclude that the response of C and N concentrations in organic matter to acid treatment in environmental materials is neither negligible nor systematic. © 2011 Elsevier B.V.link_to_subscribed_fulltex
Linking hydrogeochemistry to nitrate abundance in groundwater in agricultural settings in Ireland
peer-reviewedNitrate (NO3-âN) contamination of groundwater and associated surface waters is an increasingly important global issue with multiple impacts on terrestrial, aquatic and atmospheric environments. Investigation of the distribution of hydrogeochemical variables and their connection with the occurrence of NO3-âN provides better insights into the prediction of the environmental risk associated with nitrogen use within agricultural systems. The research objective was to evaluate the effect of hydrogeological setting on agriculturally derived groundwater NO3-âN occurrence. Piezometers (n = 36) were installed at three depths across four contrasting agricultural research sites. Groundwater was sampled monthly for chemistry and dissolved gases, between February 2009 and January 2011. Mean groundwater NO3-âN ranged 0.7â14.6 mg Lâ1, with site and groundwater depth being statistically significant (p < 0.001). Unsaturated zone thickness and saturated hydraulic conductivity (Ksat) were significantly correlated with dissolved oxygen (DO) and redox potential (Eh) across sites. Groundwater NO3-âN occurrence was significantly negatively related to DOC and methane and positively related with Eh and Ksat. Reduction of NO3-âN started at Eh potentials <150 mV while significant nitrate reduction occurred <100 mV. Indications of heterotrophic and autotrophic denitrification were observed through elevated dissolved organic carbon (DOC) and oxidation of metal bound sulphur, as indicated by sulphate (SO42-). Land application of waste water created denitrification hot spots due to high DOC losses. Hydrogeological settings significantly influenced groundwater nitrate occurrence and suggested denitrification as the main control.Department of Agriculture, Food
and the Marine Ireland - Research Stimulus
Fund Programme (Grant RSF 06383); Department of Civil, Structural and Environmental Engineering, Trinity College Dublin
Prospective study of enhanced recovery after surgery protocol in children undergoing reconstructive operations
BACKGROUND: Enhanced recovery after surgery (ERAS) protocol is a set of peri-operative strategies to increase speed of recovery. ERAS is well established in adults but has not been well studied in children.
OBJECTIVE: The purpose of the current study was to establish the safety and efficacy of an ERAS protocol in pediatric urology patients undergoing reconstructive operations. It was hypothesized that ERAS would reduce length of stay and decrease complications when compared with historical controls.
STUDY DESIGN: Institutional Review Board approval was obtained to prospectively enroll patients agedpreparation, administration of pre-operative oral carbohydrate liquid, avoidance of opioids, regional anesthesia, laparoscopy when feasible, no postoperative nasogastric tube, early feeding, and early removal of intravenous fluids (IVF). Recent (2009-2014) historical controls were propensity matched in a 2:1 ratio on age, sex, ventriculoperitoneal shunt status and whether the patient was undergoing bladder augmentation. Outcomes were protocol adherence, length of stay (LOS), emergency department (ED) visits, re-admission within 30 days, re-operations and adverse events occurring within 90 days of surgery.
RESULTS: A total of 26 historical and 13 ERAS patients were included. Median ages were 10.4 (IQR 8.0-12.4) and 9.9 years (IQR 9.1-11), respectively (P = 0.94) (see Summary Table). There were no significant between-group differences in prior abdominal surgery (38% vs 62%), rate of augmentation (88% vs 92%) or primary diagnosis of spina bifida (both 62%). ERAS significantly improved use of pre-operative liquid load (P \u3c 0.001), avoidance of opioids (P = 0.046), early discontinuation of IVF (P \u3c 0.001), and early feeding (P \u3c 0.001). Protocol adherence improved from 8/16 (IQR 4-9) historically to 12/16 (IQR 11-12) after implementation of ERAS. LOS decreased from 8 days to 5.7 days (P = 0.520). Complications of any grade per patient decreased from 2.1 to 1.3 (OR 0.71, 95% CI 0.51-0.97). There were fewer complications per patient across all grades with ERAS. No differences were seen in emergency department (ED) visits, re-admissions and re-operations.
DISCUSSION: Implementation improved consistency of care delivered. Tenets of ERAS that appeared to drive improvements included maintenance of euvolemia through avoidance of excess fluids, multimodal analgesia, and early feeding.
CONCLUSION: ERAS decreased length of stay and 90-day complications after pediatric reconstructive surgery without increased re-admissions, re-operations or ED visits. A multicenter study will be required to confirm the potential benefits of adopting ERAS