Climate, land use, and other anthropogenic and natural drivers have the potential to influence fire dynamics in many regions. To develop a mechanistic understanding of the changing role of these ...drivers and their impact on atmospheric composition, long-term fire records are needed that fuse information from different satellite and in situ data streams. Here we describe the fourth version of the Global Fire Emissions Database (GFED) and quantify global fire emissions patterns during 1997–2016. The modeling system, based on the Carnegie–Ames–Stanford Approach (CASA) biogeochemical model, has several modifications from the previous version and uses higher quality input datasets. Significant upgrades include (1) new burned area estimates with contributions from small fires, (2) a revised fuel consumption parameterization optimized using field observations, (3) modifications that improve the representation of fuel consumption in frequently burning landscapes, and (4) fire severity estimates that better represent continental differences in burning processes across boreal regions of North America and Eurasia. The new version has a higher spatial resolution (0.25°) and uses a different set of emission factors that separately resolves trace gas and aerosol emissions from temperate and boreal forest ecosystems. Global mean carbon emissions using the burned area dataset with small fires (GFED4s) were 2.2 × 1015 grams of carbon per year (Pg C yr−1) during 1997–2016, with a maximum in 1997 (3.0 Pg C yr−1) and minimum in 2013 (1.8 Pg C yr−1). These estimates were 11 % higher than our previous estimates (GFED3) during 1997–2011, when the two datasets overlapped. This net increase was the result of a substantial increase in burned area (37 %), mostly due to the inclusion of small fires, and a modest decrease in mean fuel consumption (−19 %) to better match estimates from field studies, primarily in savannas and grasslands. For trace gas and aerosol emissions, differences between GFED4s and GFED3 were often larger due to the use of revised emission factors. If small fire burned area was excluded (GFED4 without the s for small fires), average emissions were 1.5 Pg C yr−1. The addition of small fires had the largest impact on emissions in temperate North America, Central America, Europe, and temperate Asia. This small fire layer carries substantial uncertainties; improving these estimates will require use of new burned area products derived from high-resolution satellite imagery. Our revised dataset provides an internally consistent set of burned area and emissions that may contribute to a better understanding of multi-decadal changes in fire dynamics and their impact on the Earth system. GFED data are available from http://www.globalfiredata.org.
Purpose
Radioguided surgery has been widely used for clinical procedures such as sentinel node resections. In the (robot-assisted) laparoscopic setting radioguidance is realized using laparoscopic ...gamma probes, which have limited maneuverability. To increase the rotational freedom, a tethered DROP-IN gamma probe was designed. Here we present the first in vivo feasibility study of this technology in prostate cancer patients.
Methods
Ten patients scheduled for a sentinel node procedure received four injections into the prostate with (indocyanine green-)
99m
Technetium-nanocolloid and underwent preoperative imaging (lymphoscintigraphy and SPECT/CT). The DROP-IN probe was inserted via the assistant port, still permitting the insertion and usage of additional laparoscopic tools.
Results
The sentinel nodes were resected using the
da Vinci
® Si robot under guidance of DROP-IN gamma tracing and fluorescence imaging. The surgeon was able to independently maneuver the DROP-IN probe using the ProGrasp® forceps of the
da Vinci
® robot and distinguish sentinel nodes from background signal (such as the injection site).
Conclusions
Overall the DROP-IN design proves to be a valuable tool for robot-assisted radioguided surgery approaches.
The present study investigated the presence of legacy and emerging per- and polyfluoroalkyl substances (PFASs) in river water collected in 2016 up- and downstream from a fluorochemical production ...plant, as well as in river water from control sites, in The Netherlands. Additionally, drinking water samples were collected from municipalities in the vicinity from the production plant, as well as in other regions in The Netherlands. The PFOA replacement chemical GenX was detected at all downstream river sampling sites with the highest concentration (812 ng/L) at the first sampling location downstream from the production plant, which was 13 times higher than concentrations of sum perfluoroalkylcarboxylic acids and perfluoroalkanesulfonates (∑PFCA+∑PFSA). Using high resolution mass spectrometry, 11 polyfluoroalkyl acids belonging to the C2n H2n F2n O2, C2n H2n+2F2n SO4 or C2n+1H2n F2n+4SO4 homologue series were detected, but only in downstream water samples. These emerging PFASs followed a similar distribution as GenX among the downstream sampling sites, suggesting the production plant as the source. Polyfluoroalkyl sulfonates (C2n H2F4n SO3) were detected in all collected river water samples, and therefore appear to be ubiquitous contaminants in Dutch rivers. GenX was also detected in drinking water collected from 3 out of 4 municipalities in the vicinity of the production plant, with highest concentration at 11 ng/L. Drinking water containing the highest level of GenX also contained two C2n H2n F2n O2 homologues.
Relapse is the most common cause of treatment failure in pediatric acute lymphoblastic leukemia (ALL) and is often difficult to predict. To explore the prognostic impact of recurrent DNA copy number ...abnormalities on relapse, we performed high-resolution genomic profiling of 34 paired diagnosis and relapse ALL samples. Recurrent lesions detected at diagnosis, including PAX5, CDKN2A and EBF1, were frequently absent at relapse, indicating that they represent secondary events that may be absent in the relapse-prone therapy-resistant progenitor cell. In contrast, deletions and nonsense mutations in IKZF1 (IKAROS) were highly enriched and consistently preserved at the time of relapse. A targeted copy number screen in an unselected cohort of 131 precursor B-ALL cases, enrolled in the dexamethasone-based Dutch Childhood Oncology Group treatment protocol ALL9, revealed that IKZF1 deletions are significantly associated with poor relapse-free and overall survival rates. Separate analysis of ALL9-treatment subgroups revealed that non-high-risk (NHR) patients with IKZF1 deletions exhibited a approximately 12-fold higher relative relapse rate than those without IKZF1 deletions. Consequently, IKZF1 deletion status allowed the prospective identification of 53% of the relapse-prone NHR-classified patients within this subgroup and, therefore, serves as one of the strongest predictors of relapse at the time of diagnosis with high potential for future risk stratification.
The refining of vegetable oils leads to the formation of 2‐ and 3‐monochloropropane‐1,2‐diol esters (2‐ and 3‐MCPD‐E), and glycidyl esters (Gly‐E). A literature review was performed aiming to provide ...up‐to‐date knowledge on mitigation strategies during oil refining that can reduce the formation of these three processing contaminants. The review used the database Scopus and covered the period from 2009 to 2017. Most of the 18 papers dealt with palm oil and two papers with vegetable oil. Most studies focused on 3‐MCPD‐E, some on Gly‐E, and none on 2‐MCPD‐E. Water degumming was able to reduce the concentrations of 3‐MCPD‐E by 84% and Gly‐E by 26%. Neutralization of the oil reduced concentrations of 3‐MCPD‐E by 81% and Gly‐E by 84%. Bleaching with synthetic magnesium silicate reduced the 3‐MCPD‐E concentration by 67%. For the deodorization step, several mitigation strategies, such as double‐deodorization, the addition of various antioxidants, or a longer deodorization time, can reduce the formations of 3‐MCPD‐E by 82% and Gly‐E by 78%. Postrefining mitigation, including the use of absorbents, enzymes, or rebleaching of the oil, has also been reported to produce desirable contaminant reduction. Postrefining treatment with calcinated zeolite was able to reduce the 3‐MCPD‐E concentration by 19% and the Gly‐E concentration by 77%. Applying combined mitigation strategies to multiple steps of oil refining is likely crucial in order to adequately reduce levels of 3‐MCPD‐E and Gly‐E.
As they descend, the autorotating seeds of maples and some other trees generate unexpectedly high lift, but how they attain this elevated performance is unknown. To elucidate the mechanisms ...responsible, we measured the three-dimensional flow around dynamically scaled models of maple and hornbeam seeds. Our results indicate that these seeds attain high lift by generating a stable leading-edge vortex (LEV) as they descend. The compact LEV, which we verified on real specimens, allows maple seeds to remain in the air more effectively than do a variety of nonautorotating seeds. LEVs also explain the high lift generated by hovering insects, bats, and possibly birds, suggesting that the use of LEVs represents a convergent aerodynamic solution in the evolution of flight performance in both animals and plants.
Leaf age structures the phenology and development of plants, as well as the evolution of leaf traits over life histories. However, a general method for efficiently estimating leaf age across forests ...and canopy environments is lacking.
Here, we explored the potential for a statistical model, previously developed for Peruvian sunlit leaves, to consistently predict leaf ages from leaf reflectance spectra across two contrasting forests in Peru and Brazil and across diverse canopy environments.
The model performed well for independent Brazilian sunlit and shade canopy leaves (R
2 = 0.75–0.78), suggesting that canopy leaves (and their associated spectra) follow constrained developmental trajectories even in contrasting forests. The model did not perform as well for mid-canopy and understory leaves (R
2 = 0.27–0.29), because leaves in different environments have distinct traits and trait developmental trajectories. When we accounted for distinct environment–trait linkages – either by explicitly including traits and environments in the model, or, even better, by re-parameterizing the spectra-only model to implicitly capture distinct trait-trajectories in different environments – we achieved a more general model that well-predicted leaf age across forests and environments (R
2 = 0.79).
Fundamental rules, linked to leaf environments, constrain the development of leaf traits and allow for general prediction of leaf age from spectra across species, sites and canopy environments.
Abstract The global rise in prevalence of obesity is not fully explained by genetics or life style factors. The developmental origins of health and disease paradigm suggests that environmental ...factors during early life could play a role. In this perspective, perinatal exposure to bisphenol A (BPA) has been indicated as a programming factor for obesity and related metabolic disorders later in life. Here we study early life programming by BPA using an experimental design that is relevant for human exposure. C57BL/6JxFVB hybrid mice were exposed during gestation and lactation via maternal feed to 8 non-toxic doses (0–3000 μg/kg body weight/day (μg/kg bw/d)) of BPA. After weaning, offspring were followed for 20 weeks without further exposure. Adult male offspring showed dose-dependent increases of body and liver weights, no effects on fat pad weights and a dose-dependent decrease in circulating glucagon. Female offspring showed a dose-dependent decrease in body weight, liver, muscle and fat pad weights, adipocyte size, serum lipids, serum leptin and adiponectin. Physical activity was decreased in exposed males and suggested to be increased in exposed females. Brown adipose tissue showed slightly increased lipid accumulation in males and lipid depletion in females, and ucp1 expression was dose-dependently increased in females. The effects in females were more reliable and robust than in males due to wide confidence intervals and potential confounding by litter size for male data. The lowest derived BMDL (lower bound of the (two-sided) 90%-confidence interval for the benchmark dose) of 233 μg/kg bw/d (for interscapular weight in females) was below the proposed BMDL of 3633 μg/kg bw/d as a basis for tolerable daily intake. Although these results suggest that BPA can program for an altered metabolic phenotype, the sexual dimorphism of effects and diversity of outcomes among studies similar in design as the present study do not mark BPA as a specific obesogen. The consistency within the complex of observed metabolic effects suggests that upstream key element(s) in energy homeostasis are modified. Sex-dependent factors contribute to the final phenotypic outcome.
Shifts in the timing of spring phenology are a central feature of global change research. Long-term observations of plant phenology have been used to track vegetation responses to climate variability ...but are often limited to particular species and locations and may not represent synoptic patterns. Satellite remote sensing is instead used for continental to global monitoring. Although numerous methods exist to extract phenological timing, in particular start-of-spring (SOS), from time series of reflectance data, a comprehensive intercomparison and interpretation of SOS methods has not been conducted. Here, we assess 10 SOS methods for North America between 1982 and 2006. The techniques include consistent inputs from the 8 km Global Inventory Modeling and Mapping Studies Advanced Very High Resolution Radiometer NDVIg dataset, independent data for snow cover, soil thaw, lake ice dynamics, spring streamflow timing, over 16 000 individual measurements of ground-based phenology, and two temperature-driven models of spring phenology. Compared with an ensemble of the 10 SOS methods, we found that individual methods differed in average day-of-year estimates by ±60 days and in standard deviation by ±20 days. The ability of the satellite methods to retrieve SOS estimates was highest in northern latitudes and lowest in arid, tropical, and Mediterranean ecoregions. The ordinal rank of SOS methods varied geographically, as did the relationships between SOS estimates and the cryospheric/hydrologic metrics. Compared with ground observations, SOS estimates were more related to the first leaf and first flowers expanding phenological stages. We found no evidence for time trends in spring arrival from ground- or model-based data; using an ensemble estimate from two methods that were more closely related to ground observations than other methods, SOS trends could be detected for only 12% of North America and were divided between trends towards both earlier and later spring.
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