57 research outputs found
The distribution of lead between sea salt dust, and lead-rich aerosols in the mid South Pacific easterlies at American Samoa
Aerosols in the South Pacific Easterlies have been sampled at American Samoa with a cascade impactor and analysed for Pb, Ba, K, Ca, Sr, and Rb by isotope dilution mass spectrometry using ultraclean procedures. Some 84% of the Pb was found in fine (†0.5 Όm) aerosols which were collected on the backup filter with an efficiency of only 33%. Sea salt and eroded terrestrial material (dust) containing 6% and <1% respectively, of the Pb (sea salt indexed by the metals K, Ca, Sr, and Rb and dust indexed by Ba) were collected on early stages of the impactor, although 65% of the dust, because of its larger size, was lost to surfaces of the rain shelter before reaching the impactor. The remaining 10% of the Pb was associated with plant leaf waxes of continental origin which produced Pb and Ba peaks on stage 4 (0.5 Ό) of the impactor
The distribution of lead between sea salt dust, and lead-rich aerosols in the mid South Pacific easterlies at American Samoa
Stoma-free survival after anastomotic leak following rectal cancer resection: worldwide cohort of 2470 patients
Background: the optimal treatment of anastomotic leak after rectal cancer resection is unclear. this worldwide cohort study aimed to provide an overview of four treatment strategies applied. Methods: Patients from 216 centres and 45 countries with anastomotic leak after rectal cancer resection between 2014 and 2018 were included. treatment was categorized as salvage surgery, faecal diversion with passive or active (vacuum) drainage, and no primary/secondary faecal diversion. The primary outcome was 1-year stoma-free survival. In addition, passive and active drainage were compared using propensity score matching (2 : 1). results: Of 2470 evaluable patients, 388 (16.0 per cent) underwent salvage surgery, 1524 (62.0 per cent) passive drainage, 278 (11.0 per cent) active drainage, and 280 (11.0 per cent) had no faecal diversion. one-year stoma-free survival rates were 13.7, 48.3, 48.2, and 65.4 per cent respectively. propensity score matching resulted in 556 patients with passive and 278 with active drainage. there was no statistically significant difference between these groups in 1-year stoma-free survival (OR 0.95, 95 per cent c.i. 0.66 to 1.33), with a risk difference of -1.1 (95 per cent c.i. -9.0 to 7.0) per cent. after active drainage, more patients required secondary salvage surgery (OR 2.32, 1.49 to 3.59), prolonged hospital admission (an additional 6 (95 per cent c.i. 2 to 10) days), and ICU admission (OR 1.41, 1.02 to 1.94). Mean duration of leak healing did not differ significantly (an additional 12 (-28 to 52) days). Conclusion: Primary salvage surgery or omission of faecal diversion likely correspond to the most severe and least severe leaks respectively. In patients with diverted leaks, stoma-free survival did not differ statistically between passive and active drainage, although the increased risk of secondary salvage surgery and ICU admission suggests residual confounding
Stoma-free Survival After Rectal Cancer Resection With Anastomotic Leakage: Development and Validation of a Prediction Model in a Large International Cohort
Objective: This study aimed to develop and validate a prediction model (STOMA-score) for one-year stoma-free survival in rectal cancer (RC) patients with anastomotic leakage (AL). Background: AL after RC resection often results in a permanent stoma. Methods: This international retrospective cohort study (TENTACLE-Rectum) encompassed 216 participating centres, and included patients who developed AL after RC surgery between 2014-2018. Clinically relevant predictors for one-year stoma-free survival were included in uni- and multivariable logistic regression models. The STOMA-score was developed and internally validated in a cohort of patients operated between 2014-2017, with subsequent temporal validation in a 2018 cohort. The discriminative power and calibration of the models' performance were evaluated. Results: This study included 2499 AL patients; 1954 in the development cohort and 545 in the validation cohort. Baseline characteristics were comparable. One-year stoma-free survival was 45.0% in the development cohort and 43.7% in the validation cohort. The following predictors were included in the STOMA-score: sex, age, ASA-classification, body mass index, clinical M-disease, neoadjuvant therapy, abdominal- and transanal approach, primary defunctioning stoma, multivisceral resection, clinical setting in which AL was diagnosed, postoperative day of AL diagnosis, abdominal contamination, anastomotic defect circumference, bowel wall ischemia, anastomotic fistula, retraction and reactivation leakage. The STOMA-score showed good discrimination and calibration (c-index 0.71, 95%CI 0.66-0.76). Conclusion: The STOMA-score consists of eighteen clinically relevant factors and estimates the individual risk for one-year stoma-free survival in patients with AL after RC surgery, which may improve patient counselling and give guidance when analyzing efficacy of different treatment strategies in future studies
Stoma-free survival after anastomotic leak following rectal cancer resection : worldwide cohort of 2470 patients
Funding Information: The TENTACLE-Rectum study was funded by Medtronic External Research Program. The authors declare no other conflict of interest.Peer reviewedPublisher PD
International Union of Pure and Applied Chemistry: Isotopic Composition of the Elements 1997.
The Commission's Subcommittee for the Isotopic Composition of the Elements (SIAM) has carried out its biennial review of isotopic compositions, as determined by mass spectrometry and other relevant methods. This involves a critical evaluation of the published literature, element by element, and forms the basis of the Table of Isotopic Compositions of the Elements as Determined by Mass Spectrometry presented here. new guidelines have been used to arrive at the uncertainties on the isotopic abundances and there are numerous changes to the Table since it was last published in 1991. Atomic Weights calculated from this table are consistent with Ar(E) values listed in the Table of Standard Atomic Weights 1997.JRC.D-Institute for Reference Materials and Measurements (Geel
High-sensitivity measurements of strontium isotopes in polar ice
Techniques have been developed to measure the isotopic composition and concentration of Sr at sub-nanogram per gram levels in polar snow and ice samples. A 84Sr spike was used to determine Sr concentrations on a single sample aliquot of a few millilitre. Microlitre scale columns of Sr-Spec resin were used to purify Sr samples. Thermal ionisation mass spectrometry (TIMS) was used to measure the Sr isotopic ratios. A single TIMS measurement of the Sr sample yielded both isotopic composition and concentration after deconvolution of spike and sample spectra. This allows isotopic variations in Sr to be used to identify source regions of crustal dust. Early Holocene and last glacial maximum ice core samples from both Antarctica and Greenland were analysed to demonstrate the applicability of the technique. Sr isotopes were analysed in 20 g sized samples of Antarctic early Holocene ice where the concentration was only 31 pg gâ1. This represents an improvement of two orders of magnitude in sample consumption over previous studies allowing for a much higher time resolution in the analysis of polar ice cores
Spatial and Temporal Variation in Isotopic Composition of Atmospheric Lead in Norwegian Moss
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