Price & Bradstock ( ) investigated the effects of a range of environmental factors (e.g., weather, terrain, forest type) and fuel age (i.e., time since last fire, time since last logging) on the ...probability on fire severity within four areas burnt in February 2009 in Victoria. The effects of time since logging effects model on the probability of crown fire in the selected model were highly significant and negative (i.e., highest probability of crown fire in recently logged forests, Supporting Information). Importantly, no significant interaction between time since logging and forest type was included. ...the negative effect of time since logging on crown fire probability occurred in all forest types and was consistent across a range of weather conditions (Supporting Information).
Treatment of fuel (e.g. prescribed fire, logging) in fire-prone ecosystems is done to reduce risks to people and their property but effects require quantification, particularly under severe weather ...conditions when the destructive potential of fires on human infrastructure is maximised. We analysed the relative effects of fuel age (i.e. indicative of the effectiveness of prescribed fire) and logging on remotely sensed (SPOT imagery) severity of fires which occurred in eucalypt forests in Victoria, Australia in 2009. These fires burned under the most severe weather conditions recorded in Australia and caused large losses of life and property. Statistical models of the probability of contrasting extremes of severity (crown fire versus fire confined to the understorey) were developed based on effects of fuel age, logging, weather, topography and forest type. Weather was the primary influence on severity, though it was reduced at low fuel ages in Moderate but not Catastrophic, Very High or Low fire-weather conditions. Probability of crown fires was higher in recently logged areas than in areas logged decades before, indicating likely ineffectiveness as a fuel treatment. The results suggest that recently burnt areas (up to 5–10 years) may reduce the intensity of the fire but not sufficiently to increase the chance of effective suppression under severe weather conditions. Since house loss was most likely under these conditions (67%), effects of prescribed burning across landscapes on house loss are likely to be small when weather conditions are severe. Fuel treatments need to be located close to houses in order to effectively mitigate risk of loss.
► Weather was the primary influence on severity in the Victorian fires of 2009. ► In the most severe weather, young fuel age did not reduce fire severity. ► In moderate weather, fire severity was lower in recently burnt areas (up to about five years). ► House loss was also most likely in severe weather. ► Therefore diverse strategies are needed to reduce fire risk.
Wildfires and hazard reduction burns produce smoke that contains pollutants including particulate matter. Particulate matter less than 2.5 µm in diameter (PM.sub.2.5) is harmful to human health, ...potentially causing cardiovascular and respiratory issues that can lead to premature deaths. PM.sub.2.5 levels depend on environmental conditions, fire behaviour and smoke dispersal patterns. Fire management agencies need to understand and predict PM.sub.2.5 levels associated with a particular fire so that pollution warnings can be sent to communities and/or hazard reduction burns can be timed to avoid the worst conditions for PM.sub.2.5 pollution.
The newly cloned proton-linked monocarboxylate transporter MCT3 was shown by Western blotting and immunofluorescence confocal
microscopy to be expressed in all muscle fibers. In contrast, MCT1 is ...expressed most abundantly in oxidative fibers but is
almost totally absent in fast-twitch glycolytic fibers. Thus MCT3 appears to be the major MCT isoform responsible for efflux
of glycolytically derived lactic acid from white skeletal muscle. MCT3 is also expressed in several other tissues requiring
rapid lactic acid efflux. The expression of both MCT3 and MCT1 was decreased by 40â60% 3 weeks after denervation of rat hind
limb muscles, whereas chronic stimulation of the muscles for 7 days increased expression of MCT1 2â3-fold but had no effect
on MCT3 expression. The kinetics and substrate and inhibitor specificities of monocarboxylate transport into cell lines expressing
only MCT3 or MCT1 have been determined. Differences in the properties of MCT1 and MCT3 are relatively modest, suggesting that
the significance of the two isoforms may be related to their regulation rather than their intrinsic properties.
Rainforests are naturally fragmented in the Northern Territory of Australia. A census of fruit and frugivorous bird abundance was taken monthly in 10 rainforest patches for 1 year and quarterly for a ...second year to investigate spatial and temporal patterns among the patches. Fruit abundance showed a marked annual cycle, with a peak around December in the wet season. Four of six bird species showed a significant seasonal fluctuation in abundance, and for three of them, these patterns were different among rainforest types. Three species also showed a significant tendency to be most abundant in the rainforest type with the most fruit in any month. We interpret these results as evidence that birds track fruit resources among rainforest patches of different types. The abundance of two of the species (figbird and pied imperial‐pigeon) was highly variable and did not reveal significantly different temporal trends among rainforest types. These species are probably even more mobile than the other species, although the data in the present study cannot be used to test this theory. The conservation of frugivorous birds and of the plants whose seeds they disperse will require the protection of networks of rainforest patches.
Smoke from wildfires poses a significant threat to affected communities. Prescribed burning is conducted to reduce the extent and potential damage of wildfires, but produces its own smoke threat. ...Planners of prescribed fires model the likely dispersion of smoke to help manage the impacts on local communities. Significant uncertainty remains about the actual smoke impact from prescribed fires, especially near the fire, and the accuracy of smoke dispersal models. To address this uncertainty, a detailed study of smoke dispersal was conducted for one small (52 ha) and one large (700 ha) prescribed fire near Appin in New South Wales, Australia, through the use of stationary and handheld pollution monitors, visual observations and rain radar data, and by comparing observations to predictions from an atmospheric dispersion model. The 52 ha fire produced a smoke plume about 800 m high and 9 km long. Particle concentrations (PM2.5) reached very high peak values (> 400 µg m−3) and high 24 h average values (> 100 µg m−3) at several locations next to or within ∼ 500 m downwind from the fire, but low levels elsewhere. The 700 ha fire produced a much larger plume, peaking at ∼ 2000 m altitude and affecting downwind areas up to 14 km away. Both peak and 24 h average PM2.5 values near the fire were lower than for the 52 ha fire, but this may be because the monitoring locations were further away from the fire. Some lofted smoke spread north against the ground-level wind direction. Smoke from this fire collapsed to the ground during the night at different times in different locations. Although it is hard to attribute particle concentrations definitively to smoke, it seems that the collapsed plume affected a huge area including the towns of Wollongong, Bargo, Oakdale, Camden and Campbelltown (∼ 1200 km2). PM2.5 concentrations up to 169 µg m−3 were recorded on the morning following the fire. The atmospheric dispersion model accurately predicted the general behaviour of both plumes in the early phases of the fires, but was poor at predicting fine-scale variation in particulate concentrations (e.g. places 500 m from the fire). The correlation between predicted and observed varied between 0 and 0.87 depending on location. The model also completely failed to predict the night-time collapse of the plume from the 700 ha fire. This study provides a preliminary insight into the potential for large impacts from prescribed fire smoke to NSW communities and the need for increased accuracy in smoke dispersion modelling. More research is needed to better understand when and why such impacts might occur and provide better predictions of pollution risk.
Glomerular filtration rate (GFR) is routinely assessed by measuring the concentrations of endogenous serum markers such as blood urea nitrogen and serum creatinine (SCr). Although widely used, these ...endogenous markers are not ideal and do not perform optimally in certain clinical settings. The purpose of this review is to critically review the potential utility of cystatin C (CysC), especially in patient populations in which CysC may have an advantage over routinely used endogenous markers of GFR.
In a narrative approach, we extensively review publications, primarily from the last 5 years, that address the development of methods to measure CysC, reference intervals, and the diagnostic accuracy of CysC to assess GFR. Between June 2000 and September 2001 Medline was searched using "cystatin c" as a textword, and articles that examined >75 individuals (except for renal transplant studies) and/or used accepted "gold standards" for assessing GFR were selected for inclusion. A total of 17 studies are reviewed that provide reference interval data for several populations. A total of 24 studies make conclusions about the utility of CysC vs SCr and/or creatinine clearance, with 20 providing data on the sensitivity and specificity of CysC for detecting impaired GFR. These publications are organized into subgroups that deal with specific patient populations or clinical situations.
This review focuses on two areas: (a) the evolution of immunoassays used to determine the concentration of CysC in serum, their analytic sensitivity, and reference intervals; and (b) the diagnostic performance of CysC against other renal markers in the general population and in specific subpopulations of patients.
Studies of reference intervals for CysC overwhelmingly demonstrated that CysC values in blood are independent of age and sex. Of the 24 studies that examined clinical utility, 15 concluded that CysC is superior to SCr, whereas 9 concluded that CysC is equivalent but provides no advantage. Summary ROC plot analysis of 20 studies that provide sensitivity and specificity data strongly suggests that CysC will be superior to SCr for detecting impaired GFR. Taken together, it is clear that CysC performs at least as well as SCr in the population at large and that it is likely to be superior to SCr in specific patient populations.
Abstract
Introduction
Aspirin and a potent platelet P2Y12 inhibitor, such as prasugrel or ticagrelor, are not always sufficient to prevent thrombus formation in patients with ST-elevation MI (STEMI), ...leading to “slow flow” or “no reflow” effects after stenting. GPIIb/IIIa inhibitors, such as eptifibatide, may help in this setting, but are not used routinely due to their bleeding risk. GPVI has critical roles in thrombosis and a minimal role in haemostasis. Here we tested whether depletion of GPVI has effects on thrombus formation after MI in an animal model and investigated the effects of a novel platelet GPVI inhibitor, glenzocimab (a Fab fragment of a monoclonal antibody), on platelet activation and thrombus formation when combined with aspirin and ticagrelor.
Methods
We used intravital microscopy in a murine model of ST-elevation myocardial infarction and ischaemia-reperfusion injury to investigate microvascular thrombosis. We investigated the antithrombotic effects of adding glenzocimab (previously known as ACT017) to blood from healthy donors and 20 patients with ACS treated with aspirin and ticagrelor. We compared the effect of glenzocimab with the GPIIb/IIIa inhibitor eptifibatide ex-vivo. We stimulated platelets with collagen and atherosclerotic plaque material that was sourced from patients undergoing carotid endarterectomy. We investigated effects on platelet aggregation, spreading, signalling, adhesion, thrombin generation, thrombus formation and clot stability ex vivo.
Results
Genetic depletion of GPVI in an animal model of myocardial infarction reduced microvascular thrombosis. Ex vivo, aspirin and ticagrelor partially inhibited atherosclerotic plaque-induced platelet aggregation (assessed by multiple electrode aggregometry) by 48% compared to control (34±3 vs. 65±4 U; P<0.001; Figure 1). Atherosclerotic plaque-induced platelet aggregation, adhesion, secretion and activation were critically dependent on platelet GPVI activation and were potently inhibited by glenzocimab. Glenzocimab alone reduced atherosclerotic plaque-induced platelet aggregation by 75% compared to control (16±4 vs. 65±4 U; P<0.001; Figure 1) and by over 95% when combined with aspirin and ticagrelor (3±1 vs 65±4 U; P<0.001; Figure 1). Furthermore, glenzocimab provided multiple synergistic antithrombotic effects when added to the blood of aspirin and ticagrelor-treated patients with ACS ex vivo. Glenzocimab and the GPIIb/IIIa inhibitor, eptifibatide, had many similar antithrombotic effects but glenzocimab had less effect on mechanisms of general haemostasis compared to eptifibatide, as assessed by ROTEM (Figure 2).
Conclusions
The addition of glenzocimab to aspirin and ticagrelor provides synergistic inhibition of multiple critical mechanisms of atherothrombosis. Glenzocimab and the GPIIb/IIIa inhibitor, eptifibatide, share many similar antithrombotic effects, although glenzocimab has less impact on mechanisms involved in haemostasis compared to eptifibatide.
Funding Acknowledgement
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Academy of Medical Sciences UK Clinical Lecturer Starter GrantRoyal Embassy of Saudi Arabia
Frugivorous birds in the Northern Territory, Australia move among patches of monsoonal rainforest and require many patches to maintain their populations. Using bird survey data from 149 rainforest ...patches and GIS coverage of all of the ca. 15,000 patches in the Northern Territory, we analyzed the relationship between the occurrence of six frugivorous bird species, patch area, and various measures of patch isolation. Rose-crowned fruit-doves (
Ptilinopus regina) and pied imperial-pigeons (
Ducula bicolor) exhibited strong relationships with a particular isolation measure: the percentage of rainforest within 50 km of the study patch. This result was not a statistical artifact of correlations between the measure and floristic or geographical variation between patches. Yellow orioles (
Oriolus flavicintus) and common koels (
Eudynamys scolopacea) were also influenced by this isolation measure, but various other factors (e.g. patch size and proximity to coastal areas) were more significant. Figbirds (
Sphecotheres viridis) and great bowerbirds (
Chlamydera nuchalis) were not particularly affected by patch isolation, and are probably not strongly dependent on rainforest. These relationships can be used to predict the consequence of destroying patches: for example, if half of the rainforest patches in the Darwin region were destroyed, our models predict that 80% of the pigeons and 90% of the doves would disappear. A threshold value was apparent for the pigeon, dove, and koel, suggesting that a critical degree of connectedness between patches over a very large area (32 km
2 of rainforest in a 7900 km
2 circle) is necessary to maintain these species.
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