An analysis of Australia's carbon pollution reduction scheme

The authors review the decision-making since the Labour Government came into office (November 2007). The Australian Government’s ‘Carbon Pollution Reduction Scheme’ White Paper (15 December 2008) proposes that an Australian Emissions Trading Scheme (AETS) be implemented in mid-2010. Acknowledging that the scheme is comprehensive, the paper finds that in many cases, Australia will take a softer approach to climate change through the AETS than the European Union ETS(EUETS). The paper assesses key issues in the White Paper such as emissions reduction targets, GHG coverage, sectoral coverage, inclusion of unlimited quantities of offsets from Kyoto international markets and exclusion of deforestation activities

Production of extended-spectrum β -lactamases and the potential indirect pathogenic role of Prevotella isolates from the cystic fibrosis respiratory microbiota

Extended-spectrum β-lactamase (ESBL) production and the prevalence of the β-lactamase-encoding gene blaTEM were determined in Prevotella isolates (n = 50) cultured from the respiratory tract of adults and young people with cystic fibrosis (CF). Time–kill studies were used to investigate the concept of passive antibiotic resistance and to ascertain whether a β-lactamase-positive Prevotella isolate can protect a recognised CF pathogen from the action of ceftazidime in vitro. The results indicated that approximately three-quarters (38/50; 76%) of Prevotella isolates produced ESBLs. Isolates positive for ESBL production had higher minimum inhibitory concentrations (MICs) of β-lactam antibiotics compared with isolates negative for production of ESBLs (P < 0.001). The blaTEM gene was detected more frequently in CF Prevotella isolates from paediatric patients compared with isolates from adults (P = 0.002), with sequence analysis demonstrating that 21/22 (95%) partial blaTEM genes detected were identical to blaTEM-116. Furthermore, a β-lactamase-positive Prevotella isolate protected Pseudomonas aeruginosa from the antimicrobial effects of ceftazidime (P = 0.03). Prevotella isolated from the CF respiratory microbiota produce ESBLs and may influence the pathogenesis of chronic lung infection via indirect methods, including shielding recognised pathogens from the action of ceftazidime

Species composition influences soil nutrient depletion and plantphysiology in prairie agroenergy feedstocks

High-diversity mixtures of perennial tallgrass prairie vegetation could be useful biomass feed-stocks for marginal farmland in the Midwestern United States. These agroenergy crops can help meet cel-lulosic agrofuel targets while also enhancing other ecosystem services on the landscape. One proposedadvantage of high-diversity prairie biomass feedstocks is that they should become nutrient limited at aslower rate than monoculture feedstocks. In this study, we examine rates of soil nutrient depletion and thephysiology and performance of a focal species (switchgrass,Panicum virgatumL.) in four prairie agroen-ergy feedstocks with different species composition and diversity. The feedstocks in this study were a1-species switchgrass monoculture, a 5-species mixture of C4grasses, a 16-species mixture of C3and C4grasses, forbs, and legumes, and a 32-species mixture of C3and C4grasses, forbs, legumes, and sedges. Toassess feedstock effects on soil, we measured changes in soil N/P/K over afive-year period. We also per-formed a greenhouse study, in which we grew switchgrass plants infield soil conditioned by each feed-stock. To assess feedstock effects on plant function, we measured four physiological traits (photosyntheticrate, chlorophyll concentration, leafflorescence, leaf N concentration) on switchgrass plants within eachfeedstock in thefield. In the soil analysis, we found that the 5-species feedstock displayed higher rates ofsoil N/P/K depletion than other feedstocks. In the greenhouse analysis, we found that switchgrass plantsgrown in soil conditioned by the 5-species feedstock were smaller than plants grown in soil conditionedby other feedstocks. In the physiological analysis, we found that switchgrass plants in the 5-species feed-stock had lower leaf N, photosynthesis, chlorophyll concentration, and higherflorescence than switchgrassplants growing in other feedstocks. Collectively, our results show that prairie agroenergy feedstocks withdifferent species composition and diversity have different rates of soil nutrient depletion, which influencesthe physiology and performance of plants within the feedstock. These differences would ultimately impactthe ecosystem services (e.g., biomass production, need for fertilizer) that these prairie agroenergyfeedstocks provide

Unintentional injuries in children with disabilities:a systematic review and meta-analysis

Children with disabilities are thought to have an increased risk of unintentional injuries, but quantitative syntheses of findings from previous studies have not been done. We conducted a systematic review and meta-analysis to assess whether pre-existing disability can increase the risk of unintentional injuries among children when they are compared to children without disability. We searched 13 electronic databases to identify original research published between 1 January 1990 and 28 February 2013. We included those studies that reported on unintentional injuries among children with pre-existing disabilities compared with children without disabilities. We conducted quality assessments and then calculated pooled odds ratios of injury using random-effects models. Fifteen eligible studies were included from 24,898 references initially identified, and there was a total sample of 83,286 children with disabilities drawn from the eligible studies. When compared with children without disabilities, the pooled OR of injury was 1.86 (95 % CI 1.65-2.10) in children with disabilities. The pooled ORs of injury were 1.28, 1.75, and 1.86 in the 0-4 years, 5-9 years, and ≥10 years of age subgroups, respectively. Compared with children without disabilities, the pooled OR was 1.75 (95 % CI 1.26-2.43) among those with International Classification of Functioning (ICF) limitations. When disability was defined as physical disabilities, the pooled OR was 2.39 (95 % CI 1.43-4.00), and among those with cognitive disabilities, the pooled OR was 1.77 (95 % CI 1.49-2.11). There was significant heterogeneity in the included studies. Compared with peers without disabilities, children with disabilities are at a significantly higher risk of injury. Teens with disabilities may be an important subgroup for future injury prevention efforts. More data are needed from low- and middle-income countries

Survival following parathyroidectomy among United States dialysis patients

Survival following parathyroidectomy among United States dialysis patients.BackgroundSecondary hyperparathyroidism (SHPTH) is highly prevalent among persons with end-stage renal disease (ESRD). SHPTH has been linked to uremic bone disease, vascular calcification, and a higher risk of death. Parathyroidectomy (PTX) can dramatically reduce parathyroid hormone (PTH) and phosphate levels; however, the relationship between PTX and survival is not known.MethodsWe conducted an observational matched cohort study utilizing data from the United States Renal Database System (USRDS) in which 4558 patients undergoing a first PTX while on hemodialysis or peritoneal dialysis were individually matched by age, race, gender, cause of ESRD, dialysis duration, prior transplantation status, and dialysis modality to 4558 control patients who did not undergo PTX. Patients were followed from the date of PTX until they died or were lost to follow-up.ResultsThe 30-day postoperative mortality rate following PTX was 3.1%. Long-term relative risks of death among patients undergoing PTX were estimated to be 10% to 15% lower than those of matched control patients not undergoing surgery. Survival curves between the 2 groups crossed 587 days following PTX. Median survival was 53.4 months (95% CI: 51.2–56.4) in the PTX group, and 46.8 months (95% CI: 44.7–48.9) in the control group.ConclusionPTX was associated with higher short-term, and lower long-term, mortality rates among U.S. patients receiving chronic dialysis. Measures to attenuate SHPTH may play an important role in reducing mortality among patients with end-stage renal disease

Barrier bednets target malaria vectors and expand the range of usable insecticides

Transmission of Plasmodium falciparum malaria parasites occurs when nocturnal Anopheles mosquito vectors feed on human blood. In Africa, where malaria burden is highest, bednets treated with pyrethroid insecticide were highly effective in preventing mosquito bites and reducing transmission, and essential to achieving unprecedented reductions in malaria until 2015 (ref. ). Since then, progress has stalled , and with insecticidal bednets losing efficacy against pyrethroid-resistant Anopheles vectors , methods that restore performance are urgently needed to eliminate any risk of malaria returning to the levels seen before their widespread use throughout sub-Saharan Africa . Here, we show that the primary malaria vector Anopheles gambiae is targeted and killed by small insecticidal net barriers positioned above a standard bednet in a spatial region of high mosquito activity but zero contact with sleepers, opening the way for deploying many more insecticides on bednets than is currently possible. Tested against wild pyrethroid-resistant A. gambiae in Burkina Faso, pyrethroid bednets with organophosphate barriers achieved significantly higher killing rates than bednets alone. Treated barriers on untreated bednets were equally effective, without significant loss of personal protection. Mathematical modelling of transmission dynamics predicted reductions in clinical malaria incidence with barrier bednets that matched those of 'next-generation' nets recommended by the World Health Organization against resistant vectors. Mathematical models of mosquito-barrier interactions identified alternative barrier designs to increase performance. Barrier bednets that overcome insecticide resistance are feasible using existing insecticides and production technology, and early implementation of affordable vector control tools is a realistic prospect

The fate of the homoctenids (Tentaculitoidea) during the Frasnian-Famennian mass extinction (Late Devonian)

The homoctenids (Tentaculitoidea) are small, conical-shelled marine animals which are amongst the most abundant and widespread of all Late Devonian fossils. They were a principal casualty of the Frasnian-Famennian (F-F, Late Devonian) mass extinction, and thus provide an insight into the extinction dynamics. Despite their abundance during the Late Devonian, they have been largely neglected by extinction studies. A number of Frasnian-Famennian boundary sections have been studied, in Poland, Germany, France, and the United States. These sections have yielded homoctenids, which allow precise recognition of the timing of the mass extinction. It is clear that the homoctenids almost disappear from the fossil record during the latest Frasnian “Upper Kellwasser Event”. The coincident extinction of this pelagic group, and the widespread development of intense marine anoxia within the water column, provides a causal link between anoxia and the F-F extinction. Most notable is the sudden demise of a group, which had been present in rock-forming densities, during this anoxic event. One new species, belonging to Homoctenus is described, but is not formally named here