Background The incidence of thyroid cancer has more than doubled in recent decades. Debate continues on whether the increasing incidence is a result of an increased detection of small neoplasms or ...other factors. Methods Using the Surveillance, Epidemiology and End Results database, we examined the overall incidence of thyroid cancer with variations based on tumor pathology, size, and stage, as well as the current surgical and adjuvant therapy of thyroid carcinoma. Results Thyroid cancer incidence increased 2.6-fold from 1973 to 2006. This change can be attributed primarily to an increase in papillary thyroid carcinoma, which increased 3.2-fold ( P < .0001). The increase in papillary thyroid carcinoma also was examined based on tumor size. Tumors ≤1 cm increased the most at a total of 441% between 1983 and 2006 or by 19.2% per year, the incidence of papillary thyroid carcinoma also increased at 12.3%/year in 1.1–2-cm tumors, 10.3%/year in 2.1–5-cm tumors, and 12.0%/year for >5-cm tumors (all P < .0001 by Cochran–Armitage trend test). We also demonstrated a positive correlation between papillary thyroid carcinoma tumor size and stage of disease (Spearman, r = 0.285, P < .0001). Operative treatment for thyroid cancer also has shifted with total thyroidectomy replacing partial thyroidectomy as the most common surgical procedure. Conclusion Contrary to other studies, our data indicate that the increasing incidence of thyroid cancer cannot be accounted for fully by an increased detection of small neoplasms. Other possible explanations for the increase in clinically significant (>1 cm) well-differentiated thyroid carcinomas should be explored.
Under the Kigali Amendment to the Montreal Protocol, new controls are being implemented to reduce emissions of HFC-23 (CHFFormula: see text), a by-product during the manufacture of HCFC-22 ...(CHClFFormula: see text). Starting in 2015, China and India, who dominate global HCFC-22 production (75% in 2017), set out ambitious programs to reduce HFC-23 emissions. Here, we estimate that these measures should have seen global emissions drop by 87% between 2014 and 2017. Instead, atmospheric observations show that emissions have increased and in 2018 were higher than at any point in history (15.9 Formula: see text). Given the magnitude of the discrepancy between expected and observation-inferred emissions, it is likely that the reported reductions have not fully materialized or there may be substantial unreported production of HCFC-22, resulting in unaccounted-for HFC-23 by-product emissions. The difference between reported and observation-inferred estimates suggests that an additional ~309 Tg Formula: see text-equivalent emissions were added to the atmosphere between 2015 and 2017.
Renewed growth of atmospheric methane Rigby, M.; Prinn, R. G.; Fraser, P. J. ...
Geophysical research letters,
November 2008, Letnik:
35, Številka:
22
Journal Article
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Following almost a decade with little change in global atmospheric methane mole fraction, we present measurements from the Advanced Global Atmospheric Gases Experiment (AGAGE) and the Australian ...Commonwealth Scientific and Industrial Research Organisation (CSIRO) networks that show renewed growth starting near the beginning of 2007. Remarkably, a similar growth rate is found at all monitoring locations from this time until the latest measurements. We use these data, along with an inverse method applied to a simple model of atmospheric chemistry and transport, to investigate the possible drivers of the rise. Specifically, the relative roles of an increase in emission rate or a decrease in concentration of the hydroxyl radical, the largest methane sink, are examined. We conclude that: 1) if the annual mean hydroxyl radical concentration did not change, a substantial increase in emissions was required simultaneously in both hemispheres between 2006 and 2007; 2) if a small drop in the hydroxyl radical concentration occurred, consistent with AGAGE methyl chloroform measurements, the emission increase is more strongly biased to the Northern Hemisphere.
The neutrophil-lymphocyte ratio (NLR) is an inexpensive and useful inflammatory marker that incorporates the balance of the innate (neutrophil) and adaptive (lymphocyte) immune responses. Data exist ...on the association between NLR and mortality in various coronary diseases and in cancer surgery, but there is a paucity of data on the impact of preoperative NLR on vascular surgical outcomes. The aim of this study was to evaluate the relationship between preoperative NLR and elective endovascular aortic aneurysm repair (EVAR) outcome.
A retrospective review of all patients who underwent elective EVAR at a single institution between 2010 and 2018 was conducted (n = 373). Only patients who had a preoperative complete blood count with differential within 30 days of their operation were included. The NLR was computed by dividing the absolute neutrophil count by the absolute lymphocyte count. A receiver operating characteristic curve was used to determine the optimal cutoff value of NLR with the strongest association with mortality. NLR was dichotomized so that patients with NLR above the threshold were at increased risk of mortality compared with those below it. Continuous variables were analyzed using Wilcoxon nonparametric signed-rank test and categorical variables with the Fisher exact test. A comparison of NLR and mortality was completed using Kaplan-Meier survival analysis. Cox regression analysis was used to evaluate factors associated with mortality through 5-year follow-up.
Overall, 108 patients were included in this study. An NLR ≥ 4.0 was found to be associated with mortality (P < .0001). Thirty-two patients composed the High-NLR (NLR ≥ 4.0) group and the remaining 76 patients formed the Low-NLR (NLR < 4.0) group. Baseline characteristics were similar between groups, except that the High-NLR group was older (77.9 vs 74.4; P = .047). At a mean of 36.4 months follow-up, the overall mortality rate was 32.4%. Although there were no differences in the perioperative period, the Kaplan-Meier estimates of mortality were significantly greater in the High-NLR group at 1, 2, and 5 years postoperatively (P < .0001). The mean preoperative NLR of the deceased was higher (5.94 ± 5.20; median, 4.75; interquartile range, 3.17-7.83) than those who survived (2.87 ± 1.61; median, 2.53; interquartile range, 1.97-3.49) (P < .0001). Secondary interventions and sac enlargement rates were similar between groups. On univariable analysis, NLR (hazard ratio HR, 1.17; 95% confidence interval CI, 1.10-1.23; P < .0001), age (HR, 1.06; 95% CI, 1.02-1.11; P = .004), and aneurysm diameter (HR, 1.04; 95% CI, 1.01-1.07; P = .003) were associated with mortality. On multivariable analysis, NLR (HR, 1.19; 95% CI, 1.12-1.27; P < .0001), age (HR, 1.06; 95% CI, 1.01-1.11; P = .026), and aneurysm diameter (HR, 1.04; 95% CI, 1.02-1.07; P = .003) were associated with mortality.
Patients with an elevated preoperative NLR, irrespective of other comorbidities, may represent a previously unrecognized subset of patients who are at heightened risk of mortality after elective EVAR. A complete blood count with differential is an inexpensive test that may be used as a prognostic indicator for outcome after EVAR. Further research is warranted to identify clinical, pathological, or anatomical factors associated with an elevated NLR and to determine modifiable factors, which may help improve long-term survival.
Permafrost and methane hydrates are large, climate-sensitive old carbon reservoirs that have the potential to emit large quantities of methane, a potent greenhouse gas, as the Earth continues to ...warm. We present ice core isotopic measurements of methane (Δ
C, δ
C, and δD) from the last deglaciation, which is a partial analog for modern warming. Our results show that methane emissions from old carbon reservoirs in response to deglacial warming were small (<19 teragrams of methane per year, 95% confidence interval) and argue against similar methane emissions in response to future warming. Our results also indicate that methane emissions from biomass burning in the pre-Industrial Holocene were 22 to 56 teragrams of methane per year (95% confidence interval), which is comparable to today.
We present a hierarchical Bayesian method for atmospheric trace gas inversions. This method is used to estimate emissions of trace gases as well as "hyper-parameters" that characterize the ...probability density functions (PDFs) of the a priori emissions and model-measurement covariances. By exploring the space of "uncertainties in uncertainties", we show that the hierarchical method results in a more complete estimation of emissions and their uncertainties than traditional Bayesian inversions, which rely heavily on expert judgment. We present an analysis that shows the effect of including hyper-parameters, which are themselves informed by the data, and show that this method can serve to reduce the effect of errors in assumptions made about the a priori emissions and model-measurement uncertainties. We then apply this method to the estimation of sulfur hexafluoride (SF6) emissions over 2012 for the regions surrounding four Advanced Global Atmospheric Gases Experiment (AGAGE) stations. We find that improper accounting of model representation uncertainties, in particular, can lead to the derivation of emissions and associated uncertainties that are unrealistic and show that those derived using the hierarchical method are likely to be more representative of the true uncertainties in the system. We demonstrate through this SF6 case study that this method is less sensitive to outliers in the data and to subjective assumptions about a priori emissions and model-measurement uncertainties than traditional methods.
Atmospheric measurements show that emissions of hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons are now the primary drivers of the positive growth in synthetic greenhouse gas (SGHG) radiative ...forcing. We infer recent SGHG emissions and examine the impact of future emissions scenarios, with a particular focus on proposals to reduce HFC use under the Montreal Protocol. If these proposals are implemented, overall SGHG radiative forcing could peak at around 355 mW m−2 in 2020, before declining by approximately 26% by 2050, despite continued growth of fully fluorinated greenhouse gas emissions. Compared to “no HFC policy” projections, this amounts to a reduction in radiative forcing of between 50 and 240 mW m−2 by 2050 or a cumulative emissions saving equivalent to 0.5 to 2.8 years of CO2 emissions at current levels. However, more complete reporting of global HFC emissions is required, as less than half of global emissions are currently accounted for.
Key Points
Measurements of all the major synthetic greenhouse gases have been compiled
These measurements have been used to infer recent global emissions trends
Based on these trends, future emissions scenarios have been investigated
Abstract Background Open component separation has a high wound complication rate. Newer endoscopic approaches are described with no comparative trials. Methods A retrospective review (2005–2009) of ...patients undergoing open or endoscopic component separation was performed. Results Forty-four cases were identified (22 endoscopic; 22 open). All perioperative variables were the same except age (65 open vs 55 endoscopic; P < .05). Hospital length of stay was 11 days in the open group versus 8 days in the endoscopic group ( P = .09). Wound complications were 52% in the open group versus 27% in the endoscopic group ( P = .09). Wound-related interventions occurred in 45% of the open group and 33% of the endoscopic group. Hernia recurrences rates were similar (open, 32%; endoscopic, 27%; P = .99). Conclusions Open and endoscopic components separation have similar rates of recurrence. The endoscopic group had shorter lengths of stay and less major wound complications. The endoscopic approach may be the ideal technique for complex abdominal wall reconstruction.
We present atmospheric baseline growth rates from the 1970s to the present for the long-lived, strongly infrared-absorbing perfluorocarbons (PFCs) tetrafluoromethane (CF4), hexafluoroethane (C2F6), ...and octafluoropropane (C3F8) in both hemispheres, measured with improved accuracies (~1–2%) and precisions (<0.3%, or <0.2 ppt (parts per trillion dry air mole fraction), for CF4; <1.5%, or <0.06 ppt, for C2F6; <4.5%, or <0.02 ppt, for C3F8 within the Advanced Global Atmospheric Gases Experiment (AGAGE). Pre-industrial background values of 34.7±0.2 ppt CF4 and 0.1±0.02 ppt C2F6 were measured in air extracted from Greenland ice and Antarctic firn. Anthropogenic sources are thought to be primary aluminum production (CF4, C2F6, C3F8), semiconductor production (C2F6, CF4, C3F8) and refrigeration use (C3F8). Global emissions calculated with the AGAGE 2-D 12-box model are significantly higher than most previous emission estimates. The sum of CF4 and C2F6 emissions estimated from aluminum production and non-metal production are lower than observed global top-down emissions, with gaps of ~6 Gg/yr CF4 in recent years. The significant discrepancies between previous CF4, C2F6, and C3F8 emission estimates and observed global top-down emissions estimated from AGAGE measurements emphasize the need for more accurate, transparent, and complete emission reporting, and for verification with atmospheric measurements to assess the emission sources of these long-lived and potent greenhouse gases, which alter the radiative budget of the atmosphere, essentially permanently, once emitted.
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