Savannas constitute the most fire-prone biome on Earth and annual emissions from savanna-burning activities are a globally important source of greenhouse-gas (GHG) emissions. Here, we describe the ...application of a commercial fire-management program being implemented over 28 000 km
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of savanna on Aboriginal lands in northern Australia. The project combines the reinstatement of Aboriginal traditional approaches to savanna fire management - in particular a strategic, early dry-season burning program - with a recently developed emissions accounting methodology for savanna burning. Over the first 7 years of implementation, the project has reduced emissions of accountable GHGs (methane, nitrous oxide) by 37.7%, relative to the pre-project 10-year emissions baseline. In addition, the project is delivering social, biodiversity, and long-term biomass sequestration benefits. This methodological approach may have considerable potential for application in other fire-prone savanna settings.
Carbon markets afford potentially useful opportunities for supporting socially and environmentally sustainable land management programs but, to date, have been little applied in globally significant ...fire-prone savanna settings. While fire is intrinsic to regulating the composition, structure and dynamics of savanna systems, in north Australian savannas frequent and extensive late dry season wildfires incur significant environmental, production and social impacts. Here we assess the potential of market-based savanna burning greenhouse gas emissions abatement and allied carbon biosequestration projects to deliver compatible environmental and broader socio-economic benefits in a highly biodiverse north Australian setting. Drawing on extensive regional ecological knowledge of fire regime effects on fire-vulnerable taxa and communities, we compare three fire regime metrics (seasonal fire frequency, proportion of long-unburnt vegetation, fire patch-size distribution) over a 15-year period for three national parks with an indigenously (Aboriginal) owned and managed market-based emissions abatement enterprise. Our assessment indicates improved fire management outcomes under the emissions abatement program, and mostly little change or declining outcomes on the parks. We attribute improved outcomes and putative biodiversity benefits under the abatement program to enhanced strategic management made possible by the market-based mitigation arrangement. For these same sites we estimate quanta of carbon credits that could be delivered under realistic enhanced fire management practice, using currently available and developing accredited Australian savanna burning accounting methods. We conclude that, in appropriate situations, market-based savanna burning activities can provide transformative climate change mitigation, ecosystem health, and community benefits in northern Australia, and, despite significant challenges, potentially in other fire-prone savanna settings.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Tropical savannas are characterized by high primary productivity and high fire frequency, such that much of the carbon captured by vegetation is rapidly returned to the atmosphere. Hence, there have ...been suggestions that management‐driven reductions in savanna fire frequency and/or severity could significantly reduce greenhouse gas emissions and sequester carbon in tree biomass. However, a key knowledge gap is the extent to which savanna tree biomass will respond to modest shifts in fire regimes due to plausible, large‐scale management interventions. Here, we: (1) characterize relationships between the frequency and severity of fires and key demographic rates of savanna trees, based on long‐term observations in vegetation monitoring plots across northern Australia; (2) use these relationships to develop a process‐explicit demographic model describing the effects of fire on savanna tree populations; and (3) use the demographic model to address the question: to what extent is it feasible, through the strategic application of prescribed burning, to increase tree biomass in Australian tropical savannas? Our long‐term tree monitoring dataset included observations of 12,344 tagged trees in 236 plots, monitored for between 3 and 24 years. Analysis of this dataset showed that frequent high‐severity fires significantly reduced savanna tree recruitment, survival, and growth. Our demographic model suggested that: (1) despite the negative effects of frequent high‐severity fires on demographic rates, savanna tree biomass appears to be suppressed by only a relatively small amount by contemporary fire regimes, characterized by a mix of low‐ to high‐severity fires; and (2) plausible, management‐driven reductions in the frequency of high‐severity fires are likely to lead to increases in tree biomass of about 11.0 t DM ha−1 (95% CI: −1.2–20.8) over a century. Accounting for this increase in carbon storage could generate significant carbon credits, worth, on average, three times those generated annually by current greenhouse gas (methane and nitrous oxide) abatement projects, and has the potential to significantly increase the economic viability of fire/carbon projects, thereby promoting ecologically sustainable management of tropical savannas in Australia and elsewhere. This growing industry has the potential to bring much‐needed economic activity to savanna landscapes, without compromising important natural and cultural values.
•Indigenous people’s relationships to their traditional estates, and the practices involved in their care, can inform the design of payment for ecosystem service (PES) agreements.•We expand ...understandings and applications of cultural ecosystem services to show how this can build synergies between PES frameworks and the priorities of Indigenous groups.•Indigenous savanna landscape burning is used as an illustrative example to demonstrate how this framing can be applied to designing and assessing Indigenous benefits from PES agreements.
This paper draws on research conducted with Aboriginal land managers across Northern Australia to show how and why payments for ecosystem service (PES) schemes should be framed around Indigenous rights to and relationships with their traditional estates. PES schemes offer opportunities to recognize and support Aboriginal communities' land and sea management knowledge and practices, and there is strong evidence that Indigenous communities are seeking to engage with such schemes. We focus on Aboriginal savanna landscape management, particularly traditional burning practices, to extend the ecosystem services framework to recognize Indigenous values and interactions with their lands as a critical service for Indigenous well-being. Drawing on case-study analysis of PES projects negotiated to support Aboriginal fire management programs across Northern Australia, we show how cultural ecosystem services can be applied to represent the active, dynamic and often interdependent relationships inherent in Indigenous human-environment relationships.
Song complexity and singing frequency in male birds are shaped by female choice; they signal male quality because song is costly to develop and produce. The timing of song learning and the ...development of the brain structures involved occur during a period when chicks are exposed to a number of potential stressors. The quality and quantity of song produced by adults may therefore reflect the level of stress experienced during early life, a theory known as the 'developmental stress hypothesis'. We tested this hypothesis using song recordings and life-history data from an individually marked, long-term study population of wild dippers (Cinclus cinclus). The extent to which early life conditions predict adult song traits was investigated using natal brood size as a measure of sibling competition; the rate of provisioning by parents as a proxy for nutritional stress; and residuals of the linear regression between body mass and tarsus length as a measure of nestling condition. The syllable diversity in the songs of adult males was positively correlated with their body condition as nestlings, but there was no significant correlation with either provisioning rate or brood size. Provisioning rate did, however, predict song rate; males in relatively poor condition as nestlings or those raised in smaller broods which were fed more frequently by their parents sang at a higher rate in adulthood. These results support the developmental stress hypothesis and provide some of the first evidence from a wild bird of how the conditions experienced during early life impact adult song. Song traits may therefore provide females with information regarding both the current condition and developmental history of males.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background
Studies suggest that adjuvant chemotherapy should be initiated at the earliest possible time. The Eastern Cooperative Oncology Group (ECOG) and Intergroup evaluated the effect of ...perioperative fluorouracil (5-FU) on overall survival (OS) for colon cancer.
Patients and Methods
This phase III trial randomized patients to receive continuous infusional 5-FU for 7 days starting within 24 h after curative resection (arm A) or no perioperative 5-FU (arm B). Patients with Dukes’ B3 and C disease received adjuvant chemotherapy per standard of care. The primary endpoint of the trial was overall survival in patients with Dukes’ B3 and C disease. The secondary objective was to determine whether a week of perioperative infusion would affect survival in patients with Dukes’ B2 colon cancer with no additional chemotherapy.
Results
From August 1993 to May 2000, 859 patients were enrolled and 855 randomized (arm A: 427; arm B: 428). The trial was terminated early due to slow accrual. The median follow-up is 15.4 years (0.03–20.3 years). Among patients with Dukes’ B3 and C disease, there was no statistically significant difference in OS median 10.3 years (95% CI 8.4, 13.2) for perioperative chemotherapy and 9.3 years (95% CI 5.7, 12.3) for no perioperative therapy, one-sided log-rank
p
= 0.178, HR = 0.88 (95% CI 0.66, 1.16) or disease-free survival (DFS). For patients with Dukes’ B2 disease, there was also no significant difference in OS (median 16.1 versus 12.9 years) or DFS. There was no difference between treatment arms in operative complications. One week of continuous infusion of 5-FU was tolerable; 18% of arm A patients experienced grade 3 or greater toxicity.
A variety of cell surface adhesion molecules can exist as both transmembrane proteins and soluble circulating forms. Increases in the levels of soluble adhesion molecules have been correlated with a ...variety of inflammatory diseases, suggesting a pathological role. Although soluble forms are thought to result from proteolytic cleavage from the cell surface, relatively little is known about the proteases responsible for their release. In this report we demonstrate that under normal culture conditions, cells expressing vascular cell adhesion molecule 1 (VCAM-1) release a soluble form of the extracellular domain that is generated by metalloproteinase-mediated cleavage. VCAM-1 release can be rapidly simulated by phorbol 12-myristate 13-acetate (PMA), and this induced VCAM-1 shedding is mediated by metalloproteinase cleavage of VCAM-1 near the transmembrane domain. PMA-induced VCAM-1 shedding occurs as the result of activation of a specific pathway, as the generation of soluble forms of three other adhesion molecules, E-selectin, platelet-endothelial cell adhesion molecule 1, and intercellular adhesion molecule 1, are not altered by PMA stimulation. Using cells derived from genetically deficient mice, we identify tumor necrosis factor-α-converting enzyme (TACE or ADAM 17) as the protease responsible for PMA-induced VCAM-1 release, including shedding of endogenously expressed VCAM-1 by murine endothelial cells. Therefore, TACE-mediated shedding of VCAM-1 may be important for the regulation of VCAM-1 function at the cell surface.
Vps34 PI3K is thought to be the main producer of phosphatidylinositol-3-monophosphate, a lipid that controls intracellular vesicular trafficking. The organismal impact of systemic inhibition of Vps34 ...kinase activity is not completely understood. Here we show that heterozygous Vps34 kinase-dead mice are healthy and display a robustly enhanced insulin sensitivity and glucose tolerance, phenotypes mimicked by a selective Vps34 inhibitor in wild-type mice. The underlying mechanism of insulin sensitization is multifactorial and not through the canonical insulin/Akt pathway. Vps34 inhibition alters cellular energy metabolism, activating the AMPK pathway in liver and muscle. In liver, Vps34 inactivation mildly dampens autophagy, limiting substrate availability for mitochondrial respiration and reducing gluconeogenesis. In muscle, Vps34 inactivation triggers a metabolic switch from oxidative phosphorylation towards glycolysis and enhanced glucose uptake. Our study identifies Vps34 as a new drug target for insulin resistance in Type-2 diabetes, in which the unmet therapeutic need remains substantial.
Abstract Background Late onset fetal growth restriction (FGR) is often undetected prior to birth, which puts the fetus at increased risk of adverse perinatal outcomes including stillbirth. Objective ...Measuring RNA circulating in the maternal blood may provide a non-invasive insight into placental function. We examined whether measuring RNA in the maternal blood at 26-30 weeks gestation can identify pregnancies at risk of late onset FGR. We focused on RNA that are highly expressed in placenta, which we termed placental specific genes (PSG). Study design A case-control study nested within a prospective cohort of 600 women recruited at 26-30 weeks gestation. The circulating placental transcriptome in maternal blood was compared between women with late onset FGR (<5th centile at >36+6 weeks) and gestation-matched well-grown controls (20-95th centile) using microarray (n=12). Taqman Low Density Arrays (TLDA), RT - PCR and digital PCR were used to validate the microarray findings (FGR n=40, controls n=80). Results 40 women developed late onset FGR (birthweight 2574g+/-338, 2nd centile) and were matched to 80 well grown controls (birthweight 3415g,+/-339, 53rd centile p<0.05). Operative delivery and neonatal admission were higher in the FGR cohort (45% vs 23%, p<0.05). mRNA coding 137 PSGs were detected in the maternal blood and 37 were differentially expressed in late onset FGR. Seven were significantly dysregulated with PCR validation (p<0.05). Activating transcription factor 3 (ATF3) mRNA transcripts were the most promising single biomarker at 26-30 weeks: it was increased in fetuses destined to be born FGR at term (2.1 fold vs. well grown at term, p<0.001) and correlated with the severity of FGR. Combining biomarkers improved prediction of severe late onset FGR (AUC 0.88, 0.80-0.97). A multi-marker gene expression score had a sensitivity of 79%, a specificity of 88% and a positive likelihood ratio of 6.2 for subsequent delivery of a baby <3rd centile at term. Conclusion A unique placental transcriptome is detectable in maternal blood at 26-30 weeks gestation in pregnancies destined to develop late onset FGR. Circulating placental RNA may therefore be a promising non-invasive test to identify pregnancies at risk of developing FGR at term.
Poorer socioeconomic circumstances have been linked with worse outcomes in cystic fibrosis. We assessed whether a relation exists between social deprivation and individual's clinical and health-care ...outcomes.
We did a longitudinal registry study of the UK cystic fibrosis population younger than 40 years (8055 people with 49337 observations for weight, the most commonly collected outcome, between Jan 1, 1996, and Dec 31, 2009). We assessed data for weight, height, body-mass index, percent predicted forced expiratory volume in 1 s (%FEV1), risk of Pseudomonas aeruginosa colonisation, and the use of major cystic fibrosis treatment modalities. We used mixed effects models to assess the association between small-area deprivation and clinical and health-care outcomes, adjusting for clinically important covariates. We give continuous outcomes as mean differences, and binary outcomes as odds ratios, comparing extremes of deprivation quintile.
Compared with the least deprived areas, children from the most deprived areas weighed less (standard deviation SD score -0·28, 95% CI -0·38 to -0·18), were shorter (-0·31, -0·40 to -0·21, and had a lower body-mass index (-0·13, -0·22 to -0·04), were more likely to have chronic P aeruginosa infection (odds ratio 1·89, 95% CI 1·34 to 2·66), and have a lower %FEV1 (-4·12 percentage points, 95% CI -5·01 to -3·19). These inequalities were apparent very early in life and did not widen thereafter. On a population level, after adjustment for disease severity, children in the most deprived quintile were more likely to receive intravenous antibiotics (odds ratio 2·52, 95% CI 1·92 to 3·17) and nutritional treatments (1·78, 1·44 to 2·20) compared with individuals in the least deprived quintile. Patients from the most disadvantaged areas were less likely to receive DNase or inhaled antibiotic treatment.
In the UK, children with cystic fibrosis from more disadvantaged areas have worse growth and lung function compared with children from more affluent areas, but these inequalities do not widen with advancing age. Clinicians consider deprivation status, as well as disease status, when making decisions about treatments, and this might mitigate some effects of social disadvantage.
Medical Research Council (UK).
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